Wafer clamp, wafer aging test device and wafer aging test method

Abstract

The invention relates to the technical field of semiconductor detection, in particular to a wafer clamp, a wafer aging test device and a wafer aging test method. The wafer clamp comprises a lower clamp which comprises a wafer bearing part used for bearing a wafer; the upper clamp comprises a supporting frame, a circuit board fixed on the lower side of the supporting frame and a plurality of probes extending downwards, and the circuit board is provided with a plurality of through holes; each zero chuck comprises a male head and a female head, the male head is fixed to the supporting frame and inserted into the through hole, the female head is fixed to the lower clamp, and the zero chucks have a locking state enabling the male head and the female head to be locked and a releasing state enabling the male head and the female head to be released; and in the locking state, the zero chuck tensions the upper clamp and the lower clamp, a sealed detection space for accommodating the wafer is formed between the upper clamp and the lower clamp, and the probe is conductively contacted with the wafer in the detection space.

Description

Technical Field

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

[0002] After wafer fabrication is complete, the wafer may be placed in a wafer fixture, for example, to undergo an aging test in a high pressure and high temperature environment.

[0003] Related art discloses a wafer clamp composed of an upper clamp and a lower clamp, wherein the upper clamp and the lower clamp are detachably connected via a plurality of bolt elements, thereby realizing the clamping and unclamping of the clamp. This type of wafer clamp has the problem of being inconvenient to use and affecting the efficiency of the aging test. Summary of the invention

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

[0005] In a first aspect, a wafer clamp is provided, comprising: 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, and a plurality of probes extending downward, wherein the circuit board has a plurality of through holes; 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; 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 and the lower clamp, and the probe can conductively contact the test point of the wafer in the detection space.

[0006] In some possible implementations, the upper fixture includes a protective convex ring that is disposed on the periphery of the plurality of probes and protrudes downward relative to the circuit board, the protective convex ring is directly fixed to the support frame, and the plurality of through holes are arranged along a circumferential direction on the outer peripheral side of the protective convex ring; In the locked state, the protective protrusion prevents the circuit board from contacting the lower clamp.

[0007] In some possible implementations, the plurality of pneumatic chucks are arranged along a circumferential direction on an outer peripheral side of the protective convex ring.

[0008] In some possible implementations, 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.

[0009] In some possible implementations, the third air circuit includes a fifth ventilation joint fixed to the support frame and a plurality of branch air circuits branching from the fifth ventilation joint, and the plurality of branch air circuits are respectively connected to the male connectors of the plurality of zero-point chucks.

[0010] In some possible implementations, the multiple zero-point chucks are all located outside the detection space.

[0011] In some possible implementations, the following further 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.

[0012] In a second aspect, a wafer aging test device is provided, comprising the wafer fixture as described in the first aspect.

[0013] 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, 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 tightened to 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 filled into the sealed chamber through the second gas path until the air pressure in the sealed chamber 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.

[0014] In some possible implementations, 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 portion, and a second section extending from the second ventilation joint to the other side of the wafer supporting portion, 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 sealed chamber via the second gas path until the air pressure in the sealed chamber 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.

[0015] According to the wafer clamp provided in the present application, the upper clamp and the lower clamp can be quickly clamped together in a precise relative position, the upper clamp and the lower clamp can be quickly separated, and the wafer clamp can be ensured to always have a constant zero point position, thereby helping to improve the efficiency of aging testing. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings of the embodiments will be briefly introduced below. Obviously, the drawings in the following description only relate to some embodiments of the present application, rather than limiting the present application.

[0017] Figure 1 It is a schematic diagram of an exploded view of a wafer clamp provided in one embodiment of the present application.

[0018] Figure 2 From another perspective Figure 1 Schematic diagram of a device in which the carrying handle and the fifth ventilation connector on the support frame are removed.

[0019] Figure 3 yes Figure 2 Schematic diagram of the wafer clamp after clamping.

[0020] Figure 4 yes Figure 3 Schematic cross-section diagram of .

[0021] Figure 5 yes Figure 3 Another cross-sectional schematic diagram of .

[0022] Figure 6 yes Figure 5 An enlarged view of the X1 section.

[0023] Figure 7 is a top view of the lower fixture.

[0024] Figure 8 Schematic diagram of the upper fixture.

[0025] Fig. 9 It is a three-dimensional schematic diagram of the sealing component.

[0026] Fig.10 yes Fig. 9 Side view of.

[0027] Fig.11 yes Fig.10 sectional view of .

[0028] Fig.12 yes Fig.11 Enlarged view of the X2 section.

[0029] Fig.13 It is a schematic partial cross-sectional view of a sealing component provided in another embodiment of the present application.

[0030] Fig.14 This is a flow chart of a wafer aging test method provided in one embodiment of the present application.

[0031] Description of reference numerals: 100-lower fixture, 200-upper fixture, 300-sealing member; 1-wafer carrying part, 1A-adsorption port, 1B-first air port, 1C-second air port, 1D-first ring groove; 2-First gas path; 3- first ventilation connector; 4- Second ventilation connector; 5- First paragraph; 6-Second paragraph; 7- Second gas path; 8- third ventilation connector; 9- fourth ventilation connector; 10- third paragraph; 11-Paragraph 4; 12-support frame; 13-circuit board, 13A-through hole; 14-probe; 15-conductive contacts; 16-protection convex ring; 17-first ring, 171-outer ring body, 172-inner ring body, 17A-lower annular step surface, 17B-upper annular step surface, 17C-second annular groove; 18- Second ring; 19- third ring; 20-connecting ring, 20A-third ring groove; 21-Zero point chuck; 22-male; 23-female; 24- Sealed chamber; 25-Fifth ventilation connector. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical scheme and advantages of the present application clearer, the technical scheme of the embodiment of the present application will be clearly and completely described below in conjunction with the drawings of the embodiment of the present application. Obviously, the described embodiment is a part of the embodiment of the present application, rather than all the embodiments. Based on the described embodiment of the present application, all other embodiments obtained by ordinary technicians in this field without creative work belong to the scope of protection of this application. It can be understood that, in the absence of conflict, some technical means of the various embodiments described herein can be replaced or combined with each other.

[0033] In the description of this application, if there are terms such as "first", "second", etc., they are only used to distinguish the objects described and do not have any order or technical meaning. Therefore, an object defined as "first", "second", etc. may explicitly or implicitly include one or more of the objects, and, for example, the term "first element" itself does not mean the existence of the "second element", and the term "second element" itself does not mean the existence of the "first element". In addition, "one" or "a" and similar words do not indicate a quantity limitation, but rather indicate the existence of at least one, and "multiple" means not less than two.

[0034] In the description of the present application, the terms “including”, “having” 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.

[0035] In the description of the present application, reference to "one embodiment" or "some embodiments" etc. means that one or more embodiments of the present application include a particular feature, structure or characteristic described in conjunction with the embodiment. Thus, the phrases "in one embodiment", "in some embodiments", "in some other embodiments", "in some other embodiments", etc. appearing in different places in the present 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.

[0036] Figures 1 to 12 A wafer clamp provided in an embodiment of the present application is shown, which can hold the wafer therein and provide it with a gas protection atmosphere to prevent oxidation, thereby helping a wafer aging test device to complete an aging test on the wafer in a high temperature environment.

[0037] The wafer chuck mainly includes an upper chuck 200 , a lower chuck 100 and a sealing member 300 .

[0038] The lower fixture 100 includes a disc-shaped wafer carrying part 1 (chunk) for carrying the wafer upward. The upper surface of the wafer carrying part 1 has a plurality of densely arranged suction ports 1A, and the first gas path 2 provided on the lower fixture 100 is connected to these suction ports 1A. When the wafer is placed on the upper surface of the wafer carrying part 1, the first gas path 2 can be used to transmit negative pressure to each suction port 1A, so that the wafer is adsorbed and held on the wafer carrying part 1 to stabilize the test position of the wafer in the wafer fixture.

[0039] The first air path 2 includes a first vent connector 3 and a second vent connector 4 fixed to the same side of the lower fixture 100, a first section 5 extending from the first vent connector 3 to one side of the wafer carrier 1, and a second section 6 extending from the second vent connector 4 to the other side of the wafer carrier 1, the first section 5 and the second section 6 are connected in series via the space below the aforementioned plurality of suction ports 1A, and the aforementioned one side and the other side are opposite on a diameter of the wafer carrier 1. In implementation, the first vent connector 3 and the second vent connector 4 can be connected to an external negative pressure source, so that the negative pressure source is used to provide negative pressure for adsorbing wafers to the suction port 1A of the wafer carrier 1 via the first air path 2.

[0040] The upper surface of the wafer carrier 1 also has a first gas port 1B and a second gas port 1C located on opposite sides of the aforementioned plurality of suction ports 1A, and a second gas path 7 provided on the lower fixture 100 is connected to the first gas port 1B and the second gas port 1C. In practice, the wafer to be tested positioned and placed on the wafer carrier 1 is located between the first gas port 1B and the second gas port 1C, that is, the first gas port 1B and the second gas port 1C are located on opposite sides of the wafer to be tested, respectively. The second gas path 7 is used to provide a protective gas such as nitrogen around the wafer to be tested.

[0041] The second air path 7 includes a third vent connector 8 and a fourth vent connector 9 fixed to the lower fixture 100, a third section 10 extending from the third vent connector 8 to the first air port 1B, and a fourth section 11 extending from the fourth vent connector 9 to the second air port 1C, and the third section 10 and the fourth section 11 are connected in series via the sealed chamber 24. In addition, the third vent connector 8, the fourth vent connector 9, the first vent connector 3 and the second vent connector 4 are arranged side by side on the same side of the lower fixture 100.

[0042] The upper fixture 200 is arranged on the upper side of the lower fixture 100 so as to be able to be joined to 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, Figure 1 The support frame 12 may 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 plurality of probes 14 via the conductive traces. The conductive contacts 15 are disposed on the lower surface of the circuit board 13 and arranged in four regions at the edge of the circuit board 13. The conductive contacts 15 in each region are two-dimensionally distributed in a matrix shape.

[0043] The upper fixture 200 further includes a protective convex ring 16, which extends over the entire periphery of the plurality of probes 14 and protrudes relative to the lower surface of the upper fixture 200. In this way, the protective convex ring 16 can not only protect the probes 14 in the inner periphery after the upper fixture 200 is separated from the lower fixture 100, but also, when the upper fixture 200 moves downward and intends to engage with the lower fixture 100, the upper fixture 200 and the lower fixture 100 are kept at a reliable safety distance by abutting against the upper surface of the lower fixture 100 (more specifically, the upper surface of the wafer carrying portion 1 of the lower fixture 100), that is, the upper fixture 200 is prevented from being too close to the lower fixture 100, because the excessive proximity of the two may cause the circuit board 13 to rigidly contact the lower fixture 100 and be damaged, and may also cause the contact force between the probe 14 and the wafer to be too large, causing damage to the probe 14 and the wafer, such as scratching the wafer.

[0044] The sealing member 300 is arranged around the wafer, and when the upper clamp 200 is engaged with the lower clamp 100, the sealing member 300 is pressed by the upper clamp 200 and the lower clamp 100 in the up-down direction, thereby defining a sealed chamber 24 for accommodating the wafer together with the upper clamp 200 and the lower clamp 100, and the aforementioned first gas port 1B and the second gas port 1C are located in the sealed chamber 24 and directly communicated with the sealed chamber 24. In this way, the aforementioned second gas path 7 can be used to supply a protective gas such as nitrogen into the sealed chamber 24, so that the wafer under test is placed in the protective gas atmosphere to prevent the wafer from being oxidized during the high-temperature aging test process.

[0045] In the present embodiment, the sealing member 300 is fixed to the lower jig 100 , and thus, when the upper jig 200 and the lower jig 100 are separated from each other, the sealing member 300 is separated from the upper jig 200 .

[0046] See also Figure 6 as well as Figures 9 to 12 The sealing member 300 includes a first ring 17 , a second ring 18 and a third ring 19 .

[0047] The first ring 17 is a rigid body that is detachably fastened to the lower fixture 100 via a probe. In some embodiments, the first ring 17 can be an integral structure formed by molding a polymer plastic. Such a first ring 17 has good electrical insulation properties, thereby avoiding contact with electrical components or conductive parts on the upper fixture 200 and affecting the test quality when the upper fixture 200 and the lower fixture 100 are clamped together.

[0048] The first ring 17 includes an outer ring body 171 and an inner ring body 172 integrally formed on the inner circumference of the outer ring body 171, and a lower annular step surface 17A and an upper annular step surface 17B separated by the inner ring body 172 are formed at the junction of the inner ring body 172 and the outer ring body 171, and the lower annular step surface 17A and the upper annular step surface 17B define the inner circumference of the outer ring body 171.

[0049] The second ring 18 is a flexible body with a hollow cross section, which will be elastically deformed after being subjected to force, and will recover the deformation due to its own elastic force when the force is released. The second ring 18 is arranged at the lower part of the inner ring body 172 of the first ring 17, and based on the first ring 17 being screwed to the lower clamp 100, the second ring 18 is clamped between the inner ring body 172 of the first ring 17 and the lower clamp 100 in a deformed state of being against the lower annular step surface 17A. The second ring 18 protrudes from the lower surface of the first ring 17 in a natural state without deformation.

[0050] The third ring 19 is disposed on the upper part of the inner ring body 172 of the first ring 17, and is also a flexible body with a hollow cross-section. It will produce elastic deformation after being subjected to force, and restore the deformation due to its own elastic force when the force is released. In some embodiments, the third ring 19 can be bonded and fixed to the inner ring body 172 via a high-temperature resistant adhesive to prevent the third ring 19 from detaching from the wafer clamp, especially the lower clamp 100. The cross-sections of the second ring 18 and the third ring 19 in the undeformed natural state 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.

[0051] When the upper fixture 200 is engaged with the lower fixture 100, the third ring 19 is sandwiched between the inner ring body 172 and the lower surface of the upper fixture 200 in a deformed state in which the outer circumference is against the upper annular step surface 17B and the inner circumference is against the outer circumference of the protective convex ring 16, and the protective convex ring 16 is in contact with the lower fixture 100 in the aforementioned sealed chamber 24, and the probe 14 is in contact with the test point of the wafer in the aforementioned sealed chamber 24, thereby transmitting the test signal between the circuit board 13 and the wafer. When performing the aging test, the multiple conductive contacts 15 on the circuit board 13 are used for one-to-one electrical contact with multiple external second probes, and the second probes are electrically connected to the computer device via a conductive line to transmit the test signal from the wafer to the computer device, so that the computer device analyzes the relevant indicators of the wafer based on the test signal.

[0052] 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 spacing on the circuit board 13, and the spacing between the conductive contacts 15 on the circuit board 13 is enlarged, so that these conductive contacts 15 can easily contact with the aforementioned second probe, ensuring stability and safety during the aging test. Therefore, when viewed in the up-down direction, the outer contour of the lower fixture 100 all falls inside the outer contour of the upper fixture 200, and further, all the conductive contacts 15 are located on the outside of the lower fixture 100. It can be understood that by configuring all the conductive contacts 15 on the circuit board 13 to be located on the outside of the lower fixture 100 when viewed in the up-down direction, it is easier to draw a test signal from the conductive contacts 15, because the lower fixture 100 will not interfere with the docking of the external second probe with the conductive contacts 15 in the up-down direction.

[0053] Since the second ring 18 and the third ring 19 are hollow cross-section rings, they have excellent deformation ability and have a relatively large sealing contact area with the first ring 17, the first fixture, and the second fixture after being compressed. Therefore, the aforementioned sealed chamber 24 with high airtightness can be provided, and the sealed chamber 24 can maintain a high and stable protective gas pressure (test pressure) during the aging test, thereby better inhibiting the oxidation of the wafer. In addition, based on the state that the third ring 19 is sandwiched between the inner ring body 172 and the upper fixture 200 with the outer peripheral portion abutting against the upper annular step surface 17B and the inner peripheral portion abutting against the outer peripheral surface of the protective convex ring 16, the protective convex ring 16 is also cleverly used to further increase the sealing of the third ring 19.

[0054] In other embodiments, the protective convex ring 16 can be omitted, and the rigid first ring 17 can be directly used to keep the upper clamp 200 and the lower clamp 100 at a reliable safe distance, so as to protect the probe 14 and the wafer when clamped. This design helps to simplify the structure of the wafer clamp and reduce the manufacturing cost. However, compared with Figure 6 The solution shown has the disadvantage that when the upper fixture 200 is separated from the lower fixture 100, the protection of the probe 14 is reduced.

[0055] Please review Figure 6The lower fixture 100 (more specifically, the wafer carrying part 1) has a first annular groove 1D that opens upward, the first ring 17 has a second annular groove 17C that opens downward, 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, the inner peripheral side wall surface of the first annular groove 1D is staggered with the inner peripheral side wall surface of the second annular groove 17C, and 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 embedded in a deformed state in an annular space with a cross section approximately L-shaped defined by the first annular groove 1D and the second annular groove 17C. Through such a design, the second ring 18, which originally has a circular cross section, will undergo a more complex deformation (for example, not a standard elliptical or racetrack-shaped deformation) due to the shape of the first annular groove 1D and the second annular groove 17C, thereby helping to obtain a better sealing effect.

[0056] In other embodiments, Fig.13 As shown, the sealing member 300 also 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 ring groove 20A extending all around and opening toward the outer peripheral side, and the inner ring body 172 of the first ring 17 is snugly inserted into the third ring groove 20A. Through such a design, on the one hand, the third ring 19 can be prevented from falling off from the sealing member 300, and even if the sealing member 300 is detached from the wafer clamp as a whole, based on the inner ring body 172 being snugly inserted into the third ring groove 20A, the sealing member 300 can still maintain good structural integrity, avoiding the relevant parts such as the third ring 19 from being separated from the sealing member 300, and on the other hand, it also helps to enhance the sealing performance of the sealing member 300 to the sealed chamber 24, in particular, it helps to enhance the airtightness between the first ring 17 and the second ring 18 and the third ring 19.

[0057] The thickness of the connecting ring 20 can be designed to be appropriately small so that, when viewed in the radial direction, the connecting ring 20 falls entirely into the interior of the first ring 17. By such a design, the connecting ring 20 can be prevented from contacting the upper clamp 200 or the lower clamp 100 and hindering the full deformation of the third ring 19 and the second ring 18.

[0058] The engagement of the upper fixture 200 and the lower fixture 100 is achieved through four zero-point chucks 21. The zero-point chuck 21 includes a matching male head 22 and a female head 23, wherein the male head 22 is arranged on the upper fixture 200, and the female head 23 is arranged on the lower fixture 100. The zero-point chuck 21 has a locking state in which the male head 22 and the female head 23 are locked, and a releasing state in which the male head 22 and the female head 23 are released. In the locking state, the zero-point chuck 21 tightens the upper fixture 200 and the lower fixture 100 together, thereby forming a detection space for accommodating the wafer, that is, the aforementioned sealed chamber 24, and the probe 14 contacts the detection point of the wafer in the detection space. In the releasing state, the locking of 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.

[0059] The zero-point chuck 21 is a pneumatically unlockable pneumatic chuck, which is configured to switch the zero-point chuck 21 from a locked state to a released state by inflating air (providing positive pressure) to the male head 22, and to keep the zero-point chuck 21 in the locked state by stopping inflating air to the male head 22. Specifically, a third air path, which is provided in the upper clamp 200 but is omitted from the figure, is connected to the male heads 22 of these zero-point chucks 21, so that these male heads 22 are inflated by the third air path. In the locked state, the third gas circuit is in a pressure-free state, that is, balanced with the ambient atmospheric pressure, the movable part of the male head 22 is engaged with the female head 23, and the zero-point chuck 21 is in a locked state, preventing the male head 22 from separating from the female head 23. When the male head 22 is inflated via the third gas circuit, the movable part of the male head 22 moves under the action of the gas pressure, thereby disengaging from the female head 23, so that the zero-point chuck 21 is in a released state. When the male head 22 is stopped from being inflated, that is, the actuating gas pressure is stopped from being applied to the male head 22, the movable part of the male head 22 is restored to the position of being engaged with the female head 23 (for example, with the help of the force of the elastic biasing member in the male head 22).

[0060] It can be understood that due to the use of the pneumatic zero-point chuck 21, the upper clamp 200 and the lower clamp 100 can be quickly clamped together in a precise relative position, the upper clamp 200 and the lower clamp 100 can be quickly separated, and the wafer clamp can be ensured to always have a constant zero-point position, thereby helping to improve the efficiency of the aging test.

[0061] The third air circuit includes a fifth air connector 25 fixed to the upper fixture 200, and four branch air circuits (not shown) are branched from the fifth air connector 25, and the four branch air circuits are respectively connected to the male connectors 22 of the four zero-point chucks 21. In this way, only one fifth air connector 25 needs to be inflated to unlock the four zero-point chucks 21 at the same time.

[0062] As mentioned above, the area of ​​the upper fixture 200 is significantly larger than that of the lower fixture 100, which results in a significant difference in the lateral dimensions of the upper fixture 200 and the lower fixture 100, and forms an unused ineffective space at the periphery of the lower fixture 100, which easily leads to a large space occupied by the wafer fixture as a whole in the aging test cabinet, which is not conducive to the application of the wafer fixture. In order to effectively utilize the peripheral space of the lower fixture 100 and avoid further increase in the lateral dimensions of the upper fixture 200, as shown in FIG. Figure 1 As 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 .

[0063] In this embodiment, the circuit board 13 is fixed to the lower side of the support frame 12 in a stacked manner via screws, and the aforementioned protective convex ring 16 is directly fastened to the support frame 12 via screws (i.e., the protective convex ring 16 and the support frame 12 have a connection path that does not pass through the circuit board 13), and in addition, the male head 22 of each zero point chuck 21 is 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 and a tensioning force is applied to the upper clamp 200 and the lower clamp 100 to approach each other, the reaction force generated by the tensioning force will not act on the circuit board 13, thereby well protecting the circuit board 13. The circuit board 13 has four through holes 13A arranged equally in the circumferential direction on the outer peripheral side of the protective convex ring 16, and the male heads 22 of the four zero point chucks 21 are respectively inserted into the through holes 13A, thereby achieving engagement with the female head 23 below.

[0064] In addition, on the electrical connection path between the probe 14 and the conductive contact 15, there is a wire (not shown) connected to the conductive trace on the upper surface side of the circuit board 13, and the wire crosses the back side of the protective convex ring 16 on the upper surface side of the circuit board 13 to connect the probe 14 and the conductive trace. By providing the wire, the circuit board 13 body, the protective convex ring 16 and the probe 14 can be easily separated, and the protective convex ring 16 and the support frame 12 can be easily fixed directly.

[0065] The embodiment of the present application also provides a wafer aging test device including the above-mentioned wafer fixture and a method for performing an aging test on a wafer using the wafer aging test device, the method comprising: S141 , placing the wafer on the wafer supporting part 1 in a manner of covering the plurality of suction ports 1A.

[0066] In step S141, the placement angle and position of the wafer on the wafer carrier 1 can be accurately positioned using a visual system, so that the wafer is placed on the wafer carrier 1 at a specified angle, so that in subsequent operations, each probe 14 on the upper fixture 200 can accurately contact each test point on the wafer. In step S141, the upper fixture 200 and the lower fixture 100 are not yet clamped.

[0067] S142 , after replacing the air in the suction port 1A and the first gas path 2 with the protective gas, the first gas path 2 is evacuated to generate negative pressure at the suction port 1A, thereby adsorbing and holding the wafer on the wafer supporting part 1 .

[0068] The step S142 may specifically include: S142a, fill the first ventilation joint 3 with protective gas at a first rate, and extract gas from the second ventilation joint 4 at a second rate that is not less than the first rate.

[0069] Since the exhaust rate of the second vent joint 4 is not less than the filling rate of the first vent joint 3, it is possible to avoid the positive pressure at the suction port 1A causing an undesired position change of the positioned wafer.

[0070] During the process of performing step S142a, the concentration of oxygen (oxygen content) in the gas discharged from the second ventilation joint 4 can be detected in real time by using a zirconium oxide oxygen analyzer, thereby monitoring whether the original gas (i.e., air containing oxygen) in the adsorption port 1A and the first gas path 2 is exhausted. In addition, the protective gas can be high-purity nitrogen.

[0071] S142b, in response to the oxygen concentration of the gas exhausted from the second ventilation joint 4 being below the set concentration (e.g., 200 PPM), the first ventilation joint 3 is controlled to be closed. Since the second ventilation joint 4 is continuously evacuated, negative pressure is generated at each suction port 1A to suction and hold the wafer on the wafer support portion 1.

[0072] S143, in response to the air pressure at the second vent joint 4 decreasing to the first set value, the second vent joint 4 is controlled to be closed. That is, when the air pressure of the first air path 2 decreases to the first set value, the first air path 2 is closed.

[0073] At this time, since the first ventilation joint 3 and the second ventilation joint 4 are both in a closed state and the suction ports 1A of the wafer supporting part 1 are covered by the wafer, a negative pressure closed space defined by the wafer, the suction ports 1A and the first gas path 1 is formed, and the oxygen content of the gas in the negative pressure closed space is extremely small. Therefore, in the subsequent high-temperature aging test, the oxidation of the lower surface part of the wafer can be effectively suppressed.

[0074] S144, the upper clamp 200 is joined to the lower clamp 100, so as to form the aforementioned sealed chamber 24, and the clamping is completed. Specifically, when the male heads 22 and the female heads 23 of the four zero-point chucks 21 are aligned, the upper clamp 200 is controlled to move close to the lower clamp 100 to a set position, so that the male heads 22 and the female heads 23 are locked.

[0075] At this time, a sealed chamber 24 for accommodating the wafer is formed, and a plurality of probes 14 disposed on the upper fixture 200 touch each test point of the wafer downward. Therefore, the probes 14 provide a certain amount of pressing force toward the wafer supporting part 1 to the wafer under test, and the pressing force helps the wafer to maintain a stable test position.

[0076] In this embodiment, the four zero-point chucks 21 are all arranged outside the sealed chamber 24 rather than inside the sealed chamber 24. This design, on the one hand, helps to simplify the structure of the wafer clamp, and on the other hand, can prevent the gas filled into the male head 22 from accidentally entering the sealed chamber 24 during the operation process and destroying the low-oxygen atmosphere of the sealed chamber 24. Therefore, the gas used to control the locking and release of the zero-point chuck 21 does not need to use a dedicated protective gas, but can use air, which helps to save the use cost of the clamp.

[0077] S145, after the air in the sealed chamber 24 is replaced with the protective gas, the protective gas is continuously filled into the sealed chamber 24 until the air pressure in the sealed chamber 24 increases to a second set value.

[0078] In this embodiment, step S145 may specifically include: S145a, charging the protective gas into the third ventilation joint 8 at a third rate, and exhausting gas from the fourth ventilation joint 9 at a fourth rate not greater than (for example, less than) the third rate.

[0079] Since the exhaust rate of the third vent joint 8 is not greater than the filling rate of the fourth vent joint 9, it is possible to avoid the generation of negative pressure relative to the suction port 1A in the sealed chamber 24, which may cause the wafer that has been positioned to change its position undesirably. It is understandable that the protective gas filled from the third vent joint 8 enters the sealed chamber 24 through the third section 10 of the second gas path 7 and the first gas port 1B, thereby pushing the air originally in the sealed chamber 24 out through the second gas port 1C, the fourth section 11 of the second gas path 7 and the fourth vent joint 9. As this action continues, the proportion of 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 by protective gas.

[0080] During step S145a, the concentration of oxygen in the gas discharged from the fourth vent connector 9 can be detected in real time by using a zirconium oxide oxygen analyzer to monitor whether the original gas (i.e., air) in the sealed chamber 24 is exhausted. In addition, the protective gas in step S146 can also be high-purity nitrogen.

[0081] S145b, in response to the oxygen concentration of the gas discharged from the fourth vent connector 9 being below the set concentration (eg, 200 PPM), the fourth vent connector 9 is controlled to be closed. As the third vent connector 8 continues to be inflated, a positive pressure is generated in the sealed chamber 24 .

[0082] S145c, in response to the air pressure in the sealed chamber 24 reaching a second set value (eg, 0.6 MPa), the third ventilation joint 8 is controlled to be closed.

[0083] S146, heating the wafer supporting part 1 so that the wafer undergoes an aging test in a set temperature environment.

[0084] In some embodiments, the wafer carrier 1 is heated by a heating plate attached to the lower side of the wafer carrier 1, so that the heat is transferred to the lower surface of the wafer through the wafer carrier 1 on the one hand, and transferred to the high-pressure protective gas in the sealed chamber 24 through the wafer carrier 1 on the other hand, and then transferred to the upper surface of the wafer and the probe 14 by the high-pressure protective gas, so that the entire wafer under test is surrounded by a controlled high-temperature environment and undergoes an aging test. In this way, the wafer is heated in a high-pressure environment protected by the protective gas and undergoes an aging test. In addition, it can be understood that during the aging test, even if the air pressure in the suction port 1A may increase due to the temperature rise, thereby reducing its suction force, the high-pressure gas in the sealed chamber 24 that is also heated will help the wafer to be pressed toward the wafer supporting part 1, and the probe 14 that contacts and presses the wafer downward will also help the wafer to be pressed toward the wafer supporting part 1, thereby stabilizing the position of the wafer relative to the wafer supporting part 1 and the probe 14, and avoiding relative displacement between the probe 14 and the wafer. Therefore, the aforementioned first set value for initially maintaining the wafer position 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, and a plurality of probes extending downward, wherein the circuit board has a plurality of through holes; 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; 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 and the lower clamp, and the probe can conductively contact the test point of the wafer in the detection space.

2. The wafer clamp according to claim 1, characterized in that: The upper fixture comprises a protective convex ring arranged at the periphery of the plurality of probes and protruding downward relative to the circuit board, the protective convex ring is directly fixed to the support frame, and the plurality of through holes are arranged along the circumferential direction on the outer peripheral side of the protective convex ring; In the locked state, the protective protrusion prevents the circuit board from contacting the lower clamp.

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

4. 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.

5. The wafer clamp according to claim 4, 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.

6. The wafer clamp according to claim 4, characterized in that: The multiple zero-point chucks are all located outside the detection space.

7. The wafer clamp according to any one of claims 1 to 6, 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.

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

9. A wafer aging test method, characterized in that: The method is applied to the wafer aging test device as claimed in claim 8, 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 filled into the sealed chamber through the second gas path until the air pressure in the sealed chamber 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.

10. The method according to claim 9, 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 sealed chamber via the second gas path until the air pressure in the sealed chamber 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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