Electronic tester

Abstract

Disclosed is a test device that contacts a terminal on a wafer to test the wafer. The dielectric gas is used to reduce arcing between the contacts. The fixed structure and the movable structure have complementary gas interfaces that engage when the movable structure is engaged with the fixed structure. The gas cartridge has a channel block connected to the dielectric gas pressure regulator and the nitrogen pressure regulator and to the gas supply channel to selectively provide nitrogen or dielectric gas to the gas supply channel. The tray has a conductive portion to contact the rear wafer terminal, and vacuum channels, each having an enlarged portion to reduce arc.

Description

[0001] This application is a divisional application of Chinese Patent Application No. 202380089557.4, filed on December 27, 2023, with the title of “Electronic Tester”.

[0002] Cross Reference to Related Applications

[0003] This application claims priority to U.S. Provisional Patent Application No. 63 / 477,916, filed on December 30, 2022, the entire contents of which are incorporated by reference into this application. BACKGROUND 1) TECHNICAL FIELD

[0004] The present invention relates to a test apparatus for testing microelectronic circuits.

[0005] 2) DISCUSSION OF RELATED TECHNOLOGY

[0006] Microelectronic circuits are typically fabricated in and on semiconductor wafers. Such wafers are then “singulated” or “cut” into individual dies. Such dies are typically mounted onto a support substrate in order to provide them with rigidity and for electronic communication with the integrated circuits or microelectronic circuits of the dies. The final package can include packaging of the dies, and the resulting package can then be shipped to a customer.

[0007] There is a need to test the dies or packages prior to shipping them to a customer. Ideally, in order to identify defects that occur during early manufacturing, the dies should be tested at an early stage. Wafer level testing can be accomplished by providing manipulators and contactors having contacts and then using the manipulators to move the wafer so that the contacts on the wafer come into contact with the contacts on the contactors. Electrical power and electronic signals can then be provided to and from the microelectronic circuits formed in the wafer through the contactors.

[0008] According to various embodiments, the wafer includes a substrate such as a silicon substrate or a printed circuit board and one or more devices fabricated in the substrate or mounted to the substrate.

[0009] Alternatively, the wafer can be located within a movable wafer test module having an electrical interface and a thermal chuck. Electrical power and signals can be provided to and from the wafer through the electrical interface when the temperature of the wafer is thermally controlled by heating or cooling the thermal chuck.

[0010] After the wafer is singulated, it can be desirable to test the individual dies again, and it can be desirable to test the dies again after they are mounted to a support substrate. SUMMARY

[0011] A test apparatus includes first and second parts for holding a substrate therebetween, the substrate carrying a microelectronic circuit and having a plurality of terminals connected to the microelectronic circuit; a plurality of contacts on the second part, the contacts mating with the terminals for contact with the terminals; a cavity seal between the first and second parts, the cavity seal forming a closed cavity with surfaces of the first and second parts; a reduced pressure passage formed through one of the parts, the reduced pressure passage having an inlet opening at the closed cavity and an outlet opening outside the closed cavity; a reduced pressure supply connected to the reduced pressure passage, opening of the reduced pressure supply allowing gas to exit the closed cavity and closing of the reduced pressure supply preventing gas from entering the closed cavity; and an electronic tester connected to the microelectronic circuit to test the microelectronic circuit.

[0012] A test apparatus includes first and second parts for holding a substrate therebetween, the substrate carrying a microelectronic circuit and having a plurality of terminals connected to the microelectronic circuit; a plurality of contacts on the second part, the contacts mating with the terminals for contact with the terminals; a cavity seal between the first and second parts, the cavity seal forming a closed cavity with surfaces of the first and second parts; a reduced pressure passage formed through one of the parts, the reduced pressure passage having an inlet opening at the closed cavity and an outlet opening outside the closed cavity; a reduced pressure supply connected to the reduced pressure passage, opening of the reduced pressure supply allowing gas to exit the closed cavity and closing of the reduced pressure supply preventing gas from entering the closed cavity; an electronic tester connected to the microelectronic circuit to test the microelectronic circuit; a gas supply passage formed through one of the parts, the gas supply passage having an inlet opening outside the closed cavity and an outlet opening at the closed cavity; and a gas supply inlet connected to the gas supply passage, opening of the gas supply inlet allowing gas to enter the closed cavity and into a space between the contacts.

[0013] The present invention also provides a test apparatus comprising: a moveable support structure comprising a first part and a second part for holding a substrate therebetween, the substrate carrying a microelectronic circuit and having a plurality of terminals connected to the microelectronic circuit, wherein the first part is in the form of a wafer chuck having a planar face; a plurality of contacts on the second part, the contacts mating with the terminals to contact the terminals; a cavity seal between the first part and the second part, the cavity seal forming a closed cavity with the surfaces of the first part and the second part; a reduced pressure channel formed through one of the parts, the reduced pressure channel having an inlet opening at the closed cavity and an outlet opening outside the closed cavity; a reduced pressure supply connected to the reduced pressure channel, opening of the reduced pressure supply allowing gas to exit the closed cavity and closing of the reduced pressure supply preventing gas from entering the closed cavity; a first electrical interface on the moveable support structure and connected to the contacts; a moveable structure outgassing interface on the moveable structure; a fixed structure, the moveable support structure being receivable to be held by the fixed structure and removable from the fixed structure; a second electrical interface on the fixed structure, the second electrical interface being connected to the first electrical interface when the moveable structure is held by the fixed structure and the second electrical interface being disconnected from the first electrical interface when the moveable support structure is removed from the fixed structure, wherein an electronic tester is connected to the terminals through the second electrical interface, the first electrical interface and the contacts; a hot chuck on the fixed structure, wherein the planar face of the wafer chuck is moveable towards a planar face of the hot chuck; an outgassing duct forming part of the fixed structure; a fixed structure outgassing interface forming part of the fixed structure, the moveable structure outgassing interface being shaped to mate with the fixed structure outgassing interface to connect the outlet opening of the reduced pressure channel to the outgassing duct of the fixed structure when the wafer chuck is moved towards the hot chuck; and an electronic tester connected to the microelectronic circuit to test the microelectronic circuit.

[0014] The present invention also provides a test apparatus comprising: a tray for releasably holding a wafer, wherein the tray has at least a portion that is electrically conductive and has an exposed surface to contact a back wafer terminal on a back side of the wafer; a contact plate; contact plate front end contacts mounted to the contact plate, each contact plate front end contact having a surface positioned to contact a respective front wafer terminal on a front side of the wafer; an electronic tester connected to the contact plate front end contacts such that, in use, electrical current is conducted between the electronic tester and a circuit in the wafer through the front side wafer contacts and the contact plate front end contacts to test the circuit; and an electrical conductor connecting the electrically conductive portion such that, in use, the circuit is connected to the electronic tester through the back wafer contacts, the exposed surface of the electrically conductive portion, and an electrically conductive path.

[0015] The present invention also provides a test apparatus comprising: a wafer chuck; a tray for releasably holding a wafer, the tray releasably positioned on the wafer chuck, the wafer chuck having a vacuum passage therethrough, the tray having a plurality of vacuum openings therethrough, each vacuum opening connecting a back side of the wafer to the vacuum passage in the wafer chuck such that, when a vacuum is applied to the vacuum passage, the vacuum secures the back side of the wafer to the tray; a contact plate; contact plate contacts mounted to the contact plate, each contact plate contact having a surface positioned to contact a respective front wafer terminal on a front side of the wafer; and an electronic tester connected to the contact plate contacts such that, in use, electrical current is conducted between the electronic tester and a circuit in the wafer through the front side wafer contacts and the contact plate contacts to test the circuit.

[0016] The invention also provides a test apparatus comprising: a vacuum conduit defining a vacuum passageway; a wafer holder for releasably holding a wafer, the wafer holder having a plurality of vacuum openings therethrough, each vacuum opening connecting a back side of the wafer to the vacuum passageway such that when a vacuum is applied to the vacuum passageway, the vacuum secures the back side of the wafer to the wafer holder, wherein each vacuum opening has an inlet opening at the wafer, an outlet opening away from the wafer, and an enlarged portion between the inlet opening and the outlet opening to reduce arcing between the openings; a contact plate; contact plate contacts mounted to the contact plate, each contact plate contact having a surface positioned to contact a corresponding front wafer terminal on a front side of the wafer; and an electronic tester connected to the contact plate contacts such that, in use, current is conducted between the electronic tester and circuitry in the wafer through the front side wafer contacts and the contact plate contacts to test the circuitry.

[0017] The invention also provides a gas cassette comprising: a vacuum regulator connectable to a reduced pressure passageway to control gas flow through the reduced pressure passageway; a dielectric gas pressure regulator connectable to the gas supply passageway to control dielectric gas flow to the gas supply passageway; a nitrogen gas pressure regulator controlling nitrogen gas flow to the gas supply passageway; and a passageway block connected to the dielectric gas pressure regulator and the nitrogen gas pressure regulator and connectable to the gas supply passageway to selectively provide the nitrogen gas or the dielectric gas to the gas supply passageway.

[0018] The invention also provides a wafer test module comprising a movable support structure comprising first and second parts for holding a substrate therebetween, the substrate carrying microelectronic circuitry and having a plurality of terminals connected to the microelectronic circuitry; a plurality of contacts on the second part, the contacts matching the terminals for contact therewith; a cavity seal between the first and second parts, the cavity seal forming a closed cavity with surfaces of the first and second parts; a reduced pressure passage formed through one of the parts, the reduced pressure passage having an inlet opening at the closed cavity and an outlet opening outside the closed cavity; a reduced pressure supply connected to the reduced pressure passage, opening of the reduced pressure supply allowing gas to exit the closed cavity and closing of the reduced pressure supply preventing gas from entering the closed cavity; and a first electrical interface on the movable support structure and connected to the contacts for connection to a second electrical interface on a fixed structure when the movable support structure is removably held by the fixed structure.

[0019] The invention also provides a wafer test module comprising: a movable support structure comprising first and second parts for holding a substrate therebetween, the substrate carrying microelectronic circuitry and having a plurality of terminals connected to the microelectronic circuitry; a plurality of contacts on the second part, the contacts matching the terminals for contact therewith; a cavity seal between the first and second parts, the cavity seal forming a closed cavity with surfaces of the first and second parts; a reduced pressure passage formed through one of the parts, the reduced pressure passage having an inlet opening at the closed cavity and an outlet opening outside the closed cavity; a reduced pressure supply connected to the reduced pressure passage, opening of the reduced pressure supply allowing gas to exit the closed cavity and closing of the reduced pressure supply preventing gas from entering the closed cavity; a first electrical interface on the movable support structure and connected to the contacts for connection to a second electrical interface on a fixed structure when the movable support structure is removably held by the fixed structure; a gas supply passage formed through one of the parts, the gas supply passage having an inlet opening outside the closed cavity and an outlet opening at the closed cavity; and a gas supply inlet connected to the gas supply passage, opening of the gas supply inlet allowing gas to enter the closed cavity and into a space between the contacts.

[0020] The invention also provides a wafer test module comprising: a movable support structure comprising a first part and a second part for holding a substrate therebetween, the substrate carrying a microelectronic circuit and having a plurality of terminals connected to the microelectronic circuit, wherein the first part is a wafer chuck in the form of a flat piece having a flat face movable toward a flat face of a thermal chuck of a fixed structure; a plurality of contacts on the second part, the contacts mating with the terminals to contact the terminals; a cavity seal between the first part and the second part, the cavity seal forming a closed cavity with surfaces of the first part and the second part; a reduced pressure passage formed through one of the parts, the reduced pressure passage having an inlet opening at the closed cavity and an outlet opening outside the closed cavity; a reduced pressure supply connected to the reduced pressure passage, opening of the reduced pressure supply allowing gas to exit the closed cavity and closing of the reduced pressure supply preventing gas from entering the closed cavity; a first electrical interface on the movable support structure and connected to the contacts for connection to a second electrical interface on a fixed structure when the movable support structure is removably held by the fixed structure; and a movable structure outgassing interface shaped to mate with a fixed structure outgassing interface to connect the outlet opening of the reduced pressure passage to an outgassing conduit of the fixed structure when the wafer chuck is moved toward the thermal chuck.

[0021] The invention also provides a method of testing a microelectronic circuit held by a substrate, comprising holding the substrate between a first part and a second part, the second part having contacts against terminals of the substrate, the terminals connected to the microelectronic circuit; positioning a cavity seal between the first part and the second part to form a closed cavity with surfaces of the first part and the second part and the cavity seal; and transferring signals between an electronic tester and the microelectronic circuit to test the microelectronic circuit.

[0022] The invention also provides a method of testing a microelectronic circuit held by a substrate, comprising: holding the substrate between a first part and a second part, the second part having contacts against terminals of the substrate, the terminals connected to the microelectronic circuit; positioning a cavity seal between the first part and the second part to form a closed cavity with surfaces of the first part and the second part and the cavity seal; transferring signals between an electronic tester and the microelectronic circuit to test the microelectronic circuit, and allowing dielectric gas to enter the closed cavity into spaces between the contacts.

[0023] The present invention also provides a method of testing a microelectronic circuit held by a substrate, comprising: holding the substrate between a first component and a second component, the second component having contacts that abut terminals of the substrate, the terminals connected to the microelectronic circuit, wherein the first component is a wafer chuck in the form of a flat piece having a flat face; positioning a cavity seal between the first component and the second component to form an enclosed cavity through surfaces of the first component and the second component and the cavity seal; receiving the movable support structure by a fixture structure, wherein a first electrical interface on the movable support structure is connected to a second electrical interface on the fixture structure; moving the flat face of the wafer chuck toward a flat face of a thermal chuck of a fixture structure to further mate a movable structure outgassing interface with a fixture structure outgassing interface to connect the outlet opening of the reduced pressure channel to an outgassing conduit of the fixture structure; and transmitting signals between an electronic tester and the microelectronic circuit to test the microelectronic circuit, wherein the signals are transmitted between the electronic tester and the microelectronic circuit through the terminals, contacts, and first and second electrical interfaces to test the microelectronic circuit.

[0024] The present invention also provides a method of testing a wafer, comprising: holding a wafer in a tray, wherein the tray has at least a portion that is electrically conductive and has an exposed surface to contact back wafer terminals on a back side of the wafer; moving a contact plate and the tray toward each other in opposition such that surfaces of contact plate contacts mounted to the contact plate contact corresponding front wafer contacts on a front side of the wafer; conducting electrical current between an electronic tester and a circuit in the wafer through the front side wafer contacts and the contact plate contacts to test the circuit; the circuit connected to the electronic tester through the back wafer terminals, the exposed surface of the electrically conductive portion, and the electrically conductive path; and removing the wafer from the tray.

[0025] The present invention also provides a method of testing a wafer, comprising: holding a wafer in a tray; positioning the tray on a chuck; applying a vacuum to a vacuum channel through the wafer chuck, the tray having a plurality of vacuum openings therethrough, each vacuum opening connecting a back side of the wafer to the vacuum channel in the wafer chuck such that the vacuum secures the back side of the wafer to the tray; moving a contact plate and the tray in opposition toward each other such that surfaces of contact plate contacts mounted to the contact plate contact corresponding front wafer contacts on a front side of the wafer; conducting electrical current between an electronic tester and a circuit in the wafer through the front side wafer contacts and the contact plate contacts to test the circuit; and removing the wafer from the tray.

[0026] The present invention also provides a method of testing a wafer, comprising releasably holding a wafer in a wafer holder having a plurality of vacuum openings therethrough, each vacuum opening connecting a back side of the wafer to a vacuum channel; applying a vacuum to the vacuum channels, the vacuum securing the back side of the wafer to the wafer holder; moving a contact plate and the tray toward each other so that a surface of contact plate contacts mounted to the contact plate contacts are in contact with corresponding front wafer contacts on a front side of the wafer; conducting electrical current between an electronic tester and circuitry in the wafer through the front side wafer contacts and the contact plate contacts to test the circuitry, wherein each vacuum opening has an inlet opening at the wafer, an outlet opening away from the wafer, and an enlarged portion between the inlet opening and the outlet opening to reduce arcing between the openings; and removing the wafer from the tray. BRIEF DESCRIPTION OF DRAWINGS

[0027] The present invention is further described by way of example with reference to the accompanying drawings in which:

[0028] Figure 1 is a cross-sectional side view of a test apparatus having slot assemblies according to one embodiment of the present invention;

[0029] Figure 2 is a cross-sectional side view of the test apparatus along line 2-2 in Figure 1 ;

[0030] Figure 3 is a cross-sectional side view of the test apparatus along line 3-3 in Figure 1 ;

[0031] Figure 4 is a cross-sectional side view of the test apparatus along line 4-4 in Figure 2 and Figure 3 ;

[0032] Figure 5A , 5B and 5C are perspective views of the test apparatus showing the insertion or removal of a movable wafer test module into or out of the oven defined by the frame;

[0033] Figure 6 is a time diagram showing how one wafer test module can be inserted and used to test wafers and then another wafer test module is inserted;

[0034] Figure 7 is a perspective view of the test apparatus showing the insertion or removal of one slot assembly;

[0035] Figure 8A and 8B are time diagrams showing the insertion or removal of a slot assembly with respect to Figures 1-7Cross-sectional side view of the described wafer test module construction using a standoff;

[0036] Figure 9A 、 9B and 10 are side views showing the apparatus for inserting and removing the movable wafer test module into and from the oven;

[0037] Figure 11 is a perspective view from above of the first wafer test module;

[0038] Figure 12 is a perspective view from below of the first wafer test module;

[0039] Figure 13 is a cross-sectional view of the first wafer test module along 13-13 in Figure 11 and 12 ;

[0040] Figure 14 is a cross-sectional view of the first wafer test module along 14-14 in Figure 13 ;

[0041] Figure 15 is a cross-sectional view of the first wafer test module along 15-15 in Figure 12 ;

[0042] Figure 16 is a view along the direction of the arrow A in Figure 15 with its components removed;

[0043] Figure 17 is a cross-sectional view of 17-17 in Figure 15 ;

[0044] Figure 18A(i) and 18A(ii) are views in the direction of the arrows A and B in Figure 15 with the latching mechanism in the unlocked configuration;

[0045] Figure 18B(i) and 18B(ii) are views similar to Figure 18A(i) and 18A(ii) with the latching mechanism in the locked position;

[0046] Figure 19 is a perspective view showing how a shim is used to set the height of the flaps of the latching mechanism;

[0047] Figure 20 is a perspective view of components of the pressure monitoring system;

[0048] Figure 21 is a perspective view of other components of the pressure monitoring system;

[0049] Figure 22A and 22B These are perspective and side views of the components of the pressure monitoring system before they are assembled.

[0050] Figure 23A and 23B Is with Figure 22A and 22B A view of the components of a similar pressure monitoring system after they have been joined together;

[0051] Figure 24 This is a block diagram showing the components of a test apparatus for introducing dielectric materials;

[0052] Figure 25 This is a top view of the slot component;

[0053] Figure 26 yes Figure 25 Cross-sectional side views of 26A-26B in the diagram;

[0054] Figure 27 yes Figure 25 Cross-sectional side views of 27A-27B in the diagram;

[0055] Figure 28 yes Figure 26 A detailed view of the area marked "C" in the middle;

[0056] Figure 29 yes Figure 27 A detailed view of the area marked "D" in the middle;

[0057] Figure 30 This is a 3D view of the slot assembly;

[0058] Figure 31 and 32 This is a partially exploded perspective view of the gas box used in the slot assembly;

[0059] Figure 33 This is a cross-sectional side view of a portion of the wafer test module and slot assembly;

[0060] Figure 34 yes Figure 33 A detailed view of the area marked "E" in the middle; and

[0061] Figure 35 and 36 yes Figure 33 The image shows two cross-sectional perspective views of the wafer chuck and tray of the wafer testing module, which are perpendicular to each other. Detailed Implementation

[0062] In the attached diagram Figure 1A test set 10 according to an embodiment of the present application is shown, which includes (i) a stationary structure including a tester 12, a frame 14, a power supply bus 16, first and second slot assemblies 18A and 18B, a tester cable 20, a power supply cable 22, cold liquid supply lines 24A, cold liquid return lines 24B, control liquid supply lines 24C, control liquid return lines 24D, vacuum lines 24E, (ii) a movable device including first and second wafer test modules 28A and 28B, and (iii) first and second wafer test modules 30A and 30B. The first and second wafer test modules 28A and 28B are described herein as "wafer test modules," and their use is described as being for testing wafers. It should be understood that the first and second wafers 28A and 28B can generally be used for testing microelectronic circuits, and can be classified as "first and second microelectronic circuit test packs 28A and 28B."

[0063] The slot assembly 18A includes a slot assembly body 32, a hot chuck 34, a temperature detector 36, a temperature changing device in the form of a heating resistor 38, a first slot assembly interface 40, and a plurality of second slot assembly interfaces, including a control interface 44, a power supply interface 46, and cold liquid supply, return, control supply, return, and vacuum interfaces 48A, 48B, 48C, 48D, and 48E.

[0064] The first slot assembly interface 40 is located within the slot assembly body 32 and is mounted to the slot assembly body 32. The second electrical interfaces in the form of the control interface 44, the power supply interface 46, and the interfaces 48A through 48E are mounted in a left wall of the slot assembly body 32.

[0065] The slot assembly 18A is insertable into the frame 14 from left to right, and is removable from the frame 14 from right to left. The tester cable 20, the power supply cable 22, and the lines 24A through 24E are manually connected to the control interface 44, the power supply interface 46, and the interfaces 48A through 48E, respectively. Prior to removing the slot assembly 18A from the frame 14, the tester cable 20, the power supply cable 22, and the lines 24A through 24E are first manually disconnected from the control interface 44, the power supply interface 46, and the interfaces 48A through 48E, respectively.

[0066] The slot assembly 18A includes a main board 60 having test electronics, a plurality of lane module boards 62 having test electronics, a flexible connector 64, and a connection board 66. The control interface 44 and the power interface 46 are connected to the main board 60, and the thermal controller 50 is mounted to the main board 60. The lane module boards 62 are electrically connected to the main board 60. The flexible connector 64 connects the lane module boards 62 to the connection board 66. Control functions are provided through electrical conductors connecting the control interface 44 to the main board 60. Power is provided to the main board 60 through the power interface 46. Both power and control are provided from the main board 60 to the lane module boards 62 through conductors. The flexible connector 64 provides conductors connecting the lane module boards 62 to the connection board 66. The connection board 66 includes conductors connecting the flexible connector 64 to the first slot assembly interface 40. The first slot assembly interface 40 is thus connected to the control interface 44 and the power interface 46 through various conductors, so that power and control can be provided to the first slot assembly interface 40 through the control interface 44 and the power interface 46.

[0067] The second slot assembly 18B includes similar components as the first slot assembly 18A, and like reference numerals indicate like components. The second slot assembly 18B is inserted into the frame 14, and the control interface 44, the power interface 46, and the interfaces 48A through 48E of the second slot assembly 18B are each manually connected to a separate set of connection components, including a separate tester cable 20, a separate power cable 22, and separate tubing 24A through 24E.

[0068] The wafer test module 28A includes a wafer test module body formed by a wafer chuck 72 and a back plate 74. The wafer 30A has a plurality of microelectronic devices formed therein. The wafer 30A is inserted into the wafer test module body between the wafer chuck 72 and the back plate 74. Wafer test module contacts 76 contact corresponding contacts (not shown) on the wafer 30A. The wafer test module 28A also includes a wafer test module interface 78 on the back plate 74. Conductors in the back plate 74 connect the wafer test module interface 78 to the wafer test module contacts 76.

[0069] The wafer test module 28A has a lip seal 77 (also referred to herein as a "differential pressure cavity seal") connected between the back plate 74 and the wafer chuck 72. A vacuum is applied to the area defined by the lip seal 77, the back plate 74, and the wafer chuck 72. The vacuum holds the wafer test module 28A together and ensures proper contact between the wafer test module contacts 76 and the contacts on the wafer 30A.

[0070] The temperature detector 36 is located in the thermal chuck 34, and is therefore close enough to the wafer 30A to detect the temperature of the wafer 30A to within five degrees Celsius, and preferably to within one or two degrees Celsius of the wafer 30A.

[0071] The slot assembly 18A also has a door 82 that is connected to the slot assembly body 32 by a hinge 84. When the door 82 is rotated to an open position, a wafer test module 28A can be inserted into the slot assembly body 32 through a door opening 86. The wafer test module 28A is then lowered onto the hot chuck 34 and the door 82 is closed. The hot chuck 34 is mounted to the slot assembly body 32. The hot chuck 34 then essentially forms a stationary holder with a wafer test station.

[0072] The slot assembly 18A also has a thermal interface cavity seal 88 between the hot chuck 34 and the wafer chuck 72. A vacuum is applied through the vacuum interface 48E and a vacuum line 90 to the area defined by the thermal interface cavity seal 88, the hot chuck 34 and the wafer chuck 72. Thus, a good thermal connection is provided between the hot chuck 34 and the wafer chuck 72. When the heater resistor 38 generates heat, the heat is conducted through the hot chuck 34 and the wafer chuck 72 to the wafer 30A. When the hot chuck 34 is at a lower temperature than the wafer 30A, heat is conducted in the opposite direction.

[0073] The wafer test module interface 78 engages the first slot assembly interface 40. Power and signals are provided to the wafer 30A through the first slot assembly interface 40, the wafer test module interface 78 and the wafer test module contacts 76. The performance of the devices within the wafer 30A is measured through the wafer test module contacts 76, the wafer test module interface 78 and the first slot assembly interface 40.

[0074] The door 82 of the slot assembly 18B is shown in the closed position. A front seal 100 is mounted on the upper surface of the slot assembly 18A and seals against the lower surface of the slot assembly 18B. A front seal 102 is mounted to the upper surface of the slot assembly 18B and seals against the lower surface of the frame 14. A continuous sealed front wall 104 is provided by the doors 82 of the slot assemblies 18A and 18B and the front seals 100 and 102.

[0075] The slot assembly 18A also includes the thermal controller 50. The temperature detector 36 is connected to the thermal controller 50 by a temperature feedback line 52. Power is provided to the heater resistor 38 through the power interface 46 and a power line 54 so that the heater resistor 38 becomes hot. The heater resistor 38 then heats the hot chuck 34 and the wafer 30A on the hot chuck 34. The heater resistor 38 is controlled by the thermal controller 50 based on the temperature detected by the temperature detector 36.

[0076] The hot chuck 34 has a thermal fluid passage 224 formed therein. The thermal fluid passage 224 holds a thermal fluid. The thermal fluid is preferably a liquid rather than a gas because a liquid is incompressible and heat convects to or from a liquid more quickly. Different thermal fluids are used for different applications and oil is used for the highest temperature applications.

[0077] Control liquid supply and return lines 226 and 228 connect opposite ends of hot fluid channel 224 to cold liquid supply and return interfaces 48C and 48D, respectively. Heating resistor 38 acts as a heater that is mounted in place of heating hot chuck 34 to heat the hot fluid. By recirculating the hot fluid through hot fluid channel 224, hot chuck 222 provides a more uniform heat distribution to hot chuck 34 and ultimately to wafer 30A. The temperature of the fluid can also be controlled to heat or cool hot chuck 34.

[0078] Test set 10 also includes a cooling system 240, a temperature control system 242, and a vacuum pump 244. Two cold liquid supply lines 24A that connect to first and second slot assemblies 18A and 18B also connect through a manifold (not shown) to cooling system 240. Additional manifolds connect cold liquid return lines 24B to cooling system 240, control liquid supply lines 24C to temperature control system 242, control liquid return lines 24D to temperature control system 242, and vacuum lines 24E to vacuum pump 244. Each slot assembly 18A or 18B has a respective cooling plate 246 that has a respective fluid channel 248. Cooling system 240 circulates fluid through fluid channels 248 to cool cooling plates 246. Cooling plates 246 then keep channel module plates 62 cool. Temperature control system 242 circulates fluid through hot fluid channel 224 to control the temperature of hot chuck 34 and to transfer heat from or to wafers 30A and 30B. Vacuum pump 244 provides air at vacuum pressure to vacuum lines 90.

[0079] Slot assembly 18A includes a separation seal 108 that is mounted to the upper surface of slot assembly body 32 and over its inner wall 106. Separation seal 108 seals with the lower surface of slot assembly 18B. Slot assembly 18B has a separation seal 110 that is mounted to the upper surface of its slot assembly body 32. Separation seal 108 seals with the lower surface of frame 14. A continuous sealed separation wall 112 is provided by inner walls 106 of slot assemblies 18A and 18B and separation seals 108 and 110.

[0080] Figure 2 Test set 10 on middle 2-2 is shown. Figure 1 Frame 14 defines a first closed loop air path 120. Air inlet and outlet openings (not shown) can be opened to change first closed loop air path 120 to an open air path where room temperature air passes through frame 14 without being recirculated. The closed loop path is particularly useful in a clean room environment because it results in less particulate material being released into the air.

[0081] The test apparatus 10 also includes a temperature changing device in the form of a first fan 122, a first fan motor 124, and a water cooler 126.

[0082] The first fan 122 and the first fan motor 124 are mounted on the upper part of the first closed-loop air path 120. The water cooler 126 is mounted to the frame 14 within the upper part of the first closed-loop air path 120.

[0083] Wafer test modules 28A and 28B are positioned together with slot assemblies 18A and 18B and are located within the lower half of the first closed-loop air path 120.

[0084] In operation, current is supplied to the first fan motor 124. The first fan motor 124 causes the first fan 122 to rotate. The first fan 122 causes air to circulate clockwise through the first closed-loop air path 120.

[0085] The water cooler 126 then cools the air in the first closed-loop air path 120. The air then flows over the slot assemblies 18A and 18B located above the wafer test modules 28A or 28B. The wafer test modules 28A or 28B are then cooled by convection.

[0086] Figure 3 It shows Figure 1 Test apparatus 10 on 3-3. Frame 14 defines a second closed-loop air path 150. Test apparatus 10 also includes a temperature changing device in the form of a second fan 152, a second fan motor 154, and a water cooler 156. Figure 2 There is no electric heater or throttle valve installed. The air inlet and outlet openings (not shown) can be opened to turn the second closed-loop air path 150 into an open air path, in which room temperature air passes through the frame 14 without being recirculated.

[0087] The closed-loop path is particularly useful in cleanroom environments because it results in less particulate material being released into the air. A second fan 152 and a second fan motor 154 are located in the upper part of the second closed-loop air path 150. A water cooler 156 is located slightly downstream of the second fan 152 within the second closed-loop air path 150. The main board 60 and channel module board 62, forming part of the slot assemblies 18A and 18B, are located in the lower half of the second closed-loop air path 150.

[0088] In operation, current is supplied to the second fan motor 154, which rotates the second fan 152. The second fan 152 then recirculates air clockwise through the second closed-loop air path 150. The air is cooled by a water cooler 156. The cooled air then passes through the motherboard 60 and the channel module board 62, causing heat to be transferred from the motherboard 60 and the channel module board 62 to the air via convection.

[0089] Figure 1 The continuous sealing separation wall 112 shown makes Figure 2 The air recirculated through the first closed-loop air path 120 is... Figure 3 The air in the second closed-loop air path 150 remains isolated. Figure 1 The continuous sealed front wall 104 shown prevents air from escaping from the first closed-loop air path 120.

[0090] like Figure 2 and 3 As shown, with Figure 1 The same cooling system 240 used in the cooling water cooler 126 is also used in the cooling water cooler. For example... Figure 4 As shown, the pressure ventilation device (plenum) 160 separates the first closed-loop air path 120 from the second closed-loop air path 150 in all areas except those provided by the continuous sealed separation wall 112. The frame 14 has a left wall 162 and a right wall 164 that further define the closed-loop air paths 120 and 150.

[0091] Figure 5A , 5B Figure 5C illustrates how wafer test modules 30C, 30D, and 30E can be inserted or removed at any time, while all other wafer test modules are used to test wafer devices and can be in various temperature ramp states. Figure 6 The concept is illustrated in more detail. At time T1, a first wafer test module is inserted into frame 14, while a second wafer test module is located outside frame 14. At time T1, heating of the first wafer test module begins. Between T1 and T2, the temperature of the first wafer test module increases from room temperature, approximately 22°C, to a test temperature 50°C to 150°C higher than room temperature at T2. At T2, power is applied to the first wafer test module, and the devices within it are tested. At T3, the second wafer test module is inserted into frame 14, and heating of the second wafer test module begins. At T4, testing of the first wafer test module is terminated. Cooling of the first wafer test module also begins at T4. At T5, the second wafer test module reaches the test temperature, and power is supplied to it, and the wafers within it are tested. At T6, the second wafer test module reaches a temperature close to room temperature and is removed from frame 14. A third wafer test module can then be inserted in place of the first wafer test module. At T7, testing of the second wafer test module is terminated, and its cooling begins. At T8, the second wafer test module has been cooled to room temperature or near room temperature and is removed from frame 14.

[0092] Different tests can be performed at different temperatures. For example, a wafer test module can be inserted and tested at room temperature. Another test can be performed as the temperature rises. Further tests can be performed at the rising temperature. Further tests can be performed as the temperature falls. Two of these tests can be a single test running from one temperature stage to the next.

[0093] like Figure 7 As shown, a slot assembly 18A can be removed or inserted into frame 14. Slot assembly 18A can be inserted or removed, while other slot assemblies in frame 14 are used for testing wafer devices, as shown in the reference... Figure 6 As stated above.

[0094] like Figure 8A The diagram also shows a signal distribution board 500, a contact plate 502, multiple wafer contact probes 504, a contact plate retainer 506, a fastener 508, and a post 510.

[0095] The signal distribution board 500 is primarily made of insulating material and has circuitry (not shown) formed therein. Contacts 512 are formed on the lower side 514 of the signal distribution board 500. A threaded opening 516 is formed in the lower side 514.

[0096] The contact plate 502 has a plurality of probe holes 518, post holes 520, and fastener holes 522 formed therethrough from the upper side 524 to the lower side 526. Each probe hole 518 has a first portion 528 and a second portion 530. When viewed in a plan view, both the first and second portions 528 and 530 are circular. The first portion 528 has a larger diameter than the second portion 530. Figure 8A When viewed in a cross-sectional side view, the diameter of the first portion 528 is larger than that of the second portion 530, resulting in the first portion 528 being wider than the second portion 530.

[0097] The post hole 520 has a first portion 534 and a second portion 536. When viewed in a plan view, both the first portion 534 and the second portion 536 are circular. The diameter of the first portion 534 is larger than the diameter of the second portion 536. Because the diameter of the first portion 534 is larger than the diameter of the second portion 536, when... Figure 8A In a cross-sectional side view, the first portion 534 is wider than the second portion 536. The first and second portions 534 and 536 have vertical sidewalls. A water platform 538 connects the vertical sidewalls of the first and second portions 534 and 536.

[0098] Each probe 504 includes a conductive holder portion 542, a coil spring 544, and first and second end pieces 546 and 548. The first end piece 546 has a first interior 550 and a first end 552. The second end piece 548 has a second interior 554 and a second end 556. The coil spring 544 and the first and second interiors 550 and 554 are held by the holder portion 542, with the coil spring 544 between the first and second interiors 550 and 554. The first and second ends 552 and 556 protrude from the upper and lower ends, respectively, of the holder portion 542.

[0099] The upper surface of the first end 552 forms a terminal 560. The lower end of the second end 556 forms a contact pad front end contact 562. The coil spring 544 and the first and second end pieces 546 and 548 are made of metal, and thus of electrically conductive material. The coil spring 544 and the first and second end pieces 546 and 548 form a conductor capable of conducting electrical current between the terminal 560 and the contact pad front end contact 562.

[0100] The respective probe is inserted into the respective probe hole 518 through the upper side 524. The second end 556 is slightly smaller than the second portion 530 so that it passes through the second portion 530 and protrudes from the lower side 526. The holder portion 542 is slightly narrower than the first portion 528, but wider than the second portion 530, to prevent the probe 504 from falling out of the lower side 526. The first end 552 still protrudes above the upper side 524 of the contact pad 502 when the probe 504 is fully inserted into the probe hole 518, and before the contact pad 502 is mounted to the signal distribution board 500.

[0101] The post 510 has a seat 564, a force transfer portion 566, and a force transmission portion 568. The post 510 is made of a single piece of metal or other material chosen for its strength compared to the strength and brittleness of the ceramic material of the contact pad 502.

[0102] The post 510 is inserted into the post hole 520 through the upper side 524. The seat 564 and the force transfer portion 566 are slightly narrower than the second portion 536. The force transmission portion 568 is slightly narrower than the first portion 534, but wider than the second portion 536. The lower surface 570 of the force transmission portion 568 abuts the platform 538. The post 510 is thus prevented from falling out of the lower side 526.

[0103] The post 510 has a surface 572 that, when the post 510 is fully inserted as shown, lies in a plane parallel to and below the surface of the lower side 526. The force transmission portion 568 has a surface 574 that, when the post 510 is fully inserted, lies in the same plane as the upper side 524. Figure 8A

[0104] ​A signal distribution plate 500 is positioned on top of the contact plate 502. Each contact 512 is in contact with a respective one of the terminals 560. Because the terminals 560 are in a plane above the plane of the upper side 524, the lower side 514 is initially spaced apart from the upper side 524.

[0105] The fastener 508 has a threaded shaft 578 and a head 580. The contact plate compression ring 506 has an annular opening 582. The contact plate compression ring 506 is positioned on a lower surface 584 of the contact plate 502. The threaded shaft 578 is inserted through the annular opening 582 from the bottom and then through the fastener hole 522. The head 580 is in contact with the lower surface of the contact plate compression ring 506. The head 580 is then turned so that the threads on the threaded shaft 578 are screwed into the threads in the threaded opening 516. The threading action moves the signal distribution plate 500 closer to the contact plate 502 and the contact plate compression ring 506. The lower side 514 eventually comes into contact with the upper side 524. The contacts 512 move the first end piece 546 down into the probe hole 518 until the terminals 560 are in the same plane as the upper side 524. The coil spring 544 is compressed and thus slightly deformed to allow the first end piece 546 to move relatively toward the second end piece 548.

[0106] The lower side 514 has a portion that stops against a surface 574 that forms part of the post 510. Because the post 510 is in close proximity to the signal distribution plate 500, the post 510 is in position to transmit force through the surface 572 to the signal distribution plate 500.

[0107] The first wafer 32A has a plurality of electronic devices formed therein. Each electronic device has a plurality of terminals 588 at an upper surface 590 of the first wafer 32A. When the back plate 74 and the first wafer 32A are brought together, the first wafer 32A is aligned with the back plate 74 to ensure that each terminal 588 is in contact with a respective one of the contact plate front contacts 562.

[0108] A vacuum pressure is created in the area between the upper surface 590 and the lower side 526 while the pressure below the lower surface 592 of the wafer chuck 72 and the upper surface 594 of the signal distribution plate 500 remains at atmospheric pressure. The pressure differential creates equal and opposite forces Fl and F2 on the signal distribution plate 500 and the wafer chuck 72.

[0109] As Figure 8BAs shown, forces F1 and F2 cause the backplate 74 to move relative to the first wafer 32A and the wafer chuck 72. The helical spring 544 compresses further to allow the second end piece 548 to move into the probe hole position 518. Each helical spring 544 overcomes its spring force deformation, for example, F3. However, force F1 is still greater than the sum of all forces F3 added together. The upper surface 590 eventually abuts against the surface 572 of the support 564. Because the post 510 is close to the signal distribution plate 500, the support 564 prevents the upper surface 590 from moving closer to and contacting the underside 526 of the contact plate 502. The first wafer 32A transfers force F4 to the support 564. The force transfer portion 566 transfers force F4 through the second portion 536 of the post hole position 520. The force transmission portion 568 receives force F4 from the force transfer portion 566 and transmits force F4 to the signal distribution plate 500 via surface 574.

[0110] Therefore, it can be seen that force F4 is not borne by contact plate 502, thus preventing stress that could damage the brittle ceramic material of contact plate 502. Instead, force F4 is directly transmitted from the electronic device in the form of the first wafer 32A to the signal distribution board 500 through pillar 510.

[0111] exist Figure 8A and 8B In the illustrated embodiment, contact plate 502 serves as a support plate having a through-hole 520. Signal distribution plate 500 serves as a backing structure on a first side of the support plate and includes at least a circuit board with contacts 512. Probe 504 serves as a conductor having a contact 562 at the front end of the contact plate for contacting a terminal 588 on an electronic device located on a second side of the support plate, opposite to the first side of the support plate. Holder portion 542 serves as a portion of a conductor held by the support plate. The conductor also has a terminal 560 connected to the contact 512 on the signal distribution plate 500. A spring in the form of a helical spring 544 is provided. Wafer chuck 72 serves as a force generating device on one side of an electronic device in the form of a first wafer 32A opposite to the support plate. The force generating device and the support plate are movable relative to each other to move the electronic device closer to the support plate and deform the spring. The column 510 has a support 564 having a surface 572 in a plane spaced apart from the surface of the support plate to prevent the electronic device from moving closer to the support plate; a force transfer portion 566 extending at least partially from the support 564 through the column hole 520; and a force transmission portion 568 extending from the force transfer portion 566, the force transmission portion 568 being held by a backing structure.

[0112] Figure 9A A portion of the test apparatus 10 is shown, which is used to insert a wafer test module into each slot assembly, such as into slot assembly 18A, and to remove it therefrom. Figure 9AThe components of the test set 10 shown are fixed structure components, including the frame 300, a portion of the first slot assembly 18A, the first slot assembly interface 40, the holding structure 302, the horizontal transport 304, the vertical transport 306, the pusher blade 308, and the locking mechanism 310.

[0113] The frame 300 includes a first mount 312 and a second mount 314 spaced apart from each other. The horizontal transport 304 is a slide mounted between the first and second mounts 312 and 314. The holding structure 302 is mounted for sliding movement along the horizontal transport 304. Opposite ends of the pusher blade 308 are mounted to the first and second mounts 312 and 314, respectively.

[0114] The locking mechanism 310 includes a connecting rod 316, a control rod 318, and a pressure rod 320. The control rod 318 is mounted to the first mount 312 at a pivot connection 322. The vertical transport 306 is a rigid beam. A connecting member 324 connects the vertical transport 306 and a center point of the pusher blade 308 to each other. The pressure rod 320 has a first link 326 rotatably connected to the control rod 318 and a second link 328 rotatably connected to one end of the vertical transport 306. In the locked configuration shown, the first link 326 is connected to the second link 328 at a pivot connection 324. Figure 9A In the unlocked configuration shown, a wire 330 connects the pivot connection 322 and the second link 328, and the first link 326 is to the left of the wire 330.

[0115] In use, the first wafer test module 28A is positioned on the holding structure 302. The first wafer test module 28A is then moved with the holding structure 302 from left to right into the first slot assembly 18A. The placement and movement of the first wafer test module 28A can be performed manually or can be performed using a robot.

[0116] The holding structure 302 is slid along the horizontal transport 304. The connecting rod 316 connects one end of the control rod 318 to the holding structure 302. As the holding structure 302 is moved in the horizontal direction along the horizontal transport 304, the connecting rod 316 causes the control rod 318 to rotate in a counterclockwise direction about the pivot connection 322.

[0117] The first link 326 rotates counterclockwise together with the control lever 318. The pressure lever 320 converts the movement of the first link 326 into the downward movement of the second link 328. Initially, the downward movement is minimal, but the vertical movement becomes more significant when the first wafer test module 28A is fully inserted into the first slot assembly 18A, and the vertical transport device 306 engages the first wafer test module 28A with the first slot assembly 18A. The horizontal transport device 304 is thus operable to move the first wafer test module 28A horizontally from a first position to a second position into the first slot assembly 18A, and the vertical transport device 306 is operable to move the first wafer test module 28A and the first slot assembly 18A relative to each other in a first vertical direction so that the slot assembly interface 40 engages with the wafer test module interface on the first wafer test module 28A.

[0118] exist Figure 9A In the diagram, control lever 318 is shown in the unlocked position, with first link 326 located on the first side of line 330 connecting pivot connection 322 and second link 328. Control lever 318 is... Figure 9A The unlock position is rotated through the compression position, in which the push rod blade 308 is deformed by the vertical conveying device 306 via the connecting part 324 by bending the push rod blade 308 against its spring force, and the first link 326 is aligned with the pivot connecting part 322 and the second link 328. The control lever 318 continues to rotate from the compression position to the locking position, as shown. Figure 9B and 10 As shown. In the locked position, the first link 326 is to the right of line 330, and therefore to the second side of line 330 opposite to the first side. Because the first link 326 has passed through line 330 and the push rod blade 308 has overcome its spring force deformation, the first wafer test module 28A is locked in position against the slot assembly interface 40.

[0119] The system can be unlocked by moving the holding structure 302 from right to left. The control lever 318 rotates clockwise, and the first link 326 moves from right to left along the line 330. The vertical transport device 306 moves upward, i.e., in a second vertical direction opposite to the first vertical direction, to release the first wafer test module 28A from the slot assembly interface 40. Further movement of the holding structure 302 along the horizontal transport device 304 removes the first wafer test module.

[0120] Figure 11 and 12 Other components of the first wafer test module 28A are shown, including a pressure relief check valve 600, a vacuum release check valve 602, components of a latching system including first, second, third and fourth latching assemblies 604A to 604D, and an electronic pressure sensor interface 606 forming part of a pressure monitoring system.

[0121] Figure 13 is a cross-sectional view along Figure 11 and 12 13-13. The pressure relief channel 608 is formed in the back plate 74. The pressure relief channel 608 has an outlet opening 610 and an intermediate location 612 that are in the same plane. The outlet opening 610 is connected to the pressure relief check valve 600. The intermediate location 612 is closer to the center point of the back plate 74 than the outlet opening 610. The pressure relief channel 608 is formed by first drilling four channels in the back plate 74 and then closing one end of three of the channels, leaving the pressure relief channel 608 formed to be completely isolated from atmospheric pressure outside the back plate 74.

[0122] Figure 14 is a cross-sectional view along Figure 13 14-14, the pressure relief channel 608 continues downward through the support plate 74 and the signal distribution plate 500 from the intermediate location 612. The pressure relief channel 608 has an inlet opening 624 that is in communication with the differential pressure cavity 622. The lip seal 77 is located in a groove in the wafer chuck 72. The differential pressure cavity 622 is formed by the wafer chuck 72 forming the lower side of the differential pressure cavity 622, the contact plate 502, the contact plate compression ring 506, and the signal distribution plate 500 forming the upper side of the differential pressure cavity 622, and the lip seal 77 forming the connection between the upper and lower sides of the differential pressure cavity 622. The lip seal 77 is completely circular and completely surrounds the contact plate 502 and the wafer located between the contact plate 502 and the wafer chuck 72.

[0123] Figure 14 The components shown form a removable support structure 626. The removable support structure 626 has a first component 628 that includes the signal distribution plate 500 and the back plate 74, and a second component 630 that includes the wafer chuck 72.

[0124] In use, the first component 628 is separated from the second component 630. A wafer is then placed on the wafer chuck 72. The first component 628 is then positioned on the second component 630. The upper periphery of the lip seal 77 is in contact with the signal distribution plate 500. The wafer is thus held in the removable support structure 626.

[0125] Now referring to Figure 13 and 14 , a pump is connected to the pressure relief check valve 600. The pressure relief check valve 600 is then opened. The pressure relief channel 608 can initially be at atmospheric pressure, and the pump subsequently lowers the pressure in the pressure relief channel 608. The differential pressure cavity 622 is exposed to a pressure that is lower than atmospheric pressure. The outer surface of the first wafer test module 28A is still exposed to atmospheric pressure. Because a pressure differential is created between the differential pressure cavity 622 and the outer surface of the first wafer test module 28A, the springs in the contact plate 502 compress, as described with reference to Figure 8BThe lip seal 77 is made of a resilient elastomeric material that allows the lip seal to compress against its spring force. Because the lip seal 77 is compressed against its spring force, an improved seal is created between the lip seal 77 and the signal distribution board 500, thereby allowing the pressure within the differential pressure cavity 622 to be maintained. The pressure relief check valve 600 is then closed, isolating the pressure relief passage 608 from the external atmospheric pressure. The pump can then be disconnected from the pressure relief check valve 600.

[0126] The first wafer test module 28A, with the wafer loaded therein, can now be moved throughout the manufacturing environment without being connected to a pump or tester. If the wafer is later needed to be removed, the pressure relief check valve 602 shown in FIG. 15-15 can be applied with a positive pressure. The pressure relief check valve 602 is spring loaded, requiring a predetermined amount of pressure to be applied before opening. Air can then flow through the pressure relief passage in the back plate 74 to the differential pressure cavity 622, and bring the differential pressure cavity 622 to atmospheric pressure. The first and second components 628 and 630 can then be separated from each other, and the wafer can be removed. When a new wafer is loaded into the first wafer test module 28A, and when it is desired to reduce the pressure within the differential pressure cavity 622 using the pressure relief check valve 600, the pressure relief check valve 602 is later closed. Figure 11 and 12 The pressure relief check valve 602 is spring loaded, requiring a predetermined amount of pressure to be applied before opening. Air can then flow through the pressure relief passage in the back plate 74 to the differential pressure cavity 622, and bring the differential pressure cavity 622 to atmospheric pressure. The first and second components 628 and 630 can then be separated from each other, and the wafer can be removed. When a new wafer is loaded into the first wafer test module 28A, and when it is desired to reduce the pressure within the differential pressure cavity 622 using the pressure relief check valve 600, the pressure relief check valve 602 is later closed.

[0127] Figure 15 is Figure 12 a cross-sectional view of 15-15 in FIG. 15. The first latch assembly 604A includes a first portion 640, a second portion 642, a connecting portion 644, an engagement mechanism 646, a tuning block 648, a locking nut 650, a spacer 652A, a washer 652B, and a snap mechanism 654.

[0128] The first portion 640 and the connecting portion 644 are machined as a single piece, and are therefore fixed to each other. The first portion 640 has a length 660 and a width 662. Only half of the width 662 is shown in cross-section. The length 660 is greater than the width 662. The length 660 is also greater than the diameter of the connecting portion 644. The first portion 640 has a tooling probe site 664 formed therein.

[0129] The second portion 642 has a body 666 and first and second wings 668A and 668B extending from the body 666. The second portion 642 has a length 670 and a width 672, including the wings 668A and 668B. Only half of the width 672 is shown in cross-section. Because the first and second wings 668A and 668B form part of the length 670 but not part of the width 672, the length 670 is much greater than the width 672. The body 666 also has an opening 674 into which the connecting portion 644 can be inserted.

[0130] The connection portion 644 includes a first portion 678 and a second portion 680. The second portion 680 has external threads formed thereon.

[0131] The engagement mechanism 646 is formed by opposing surfaces that define the width 662 of the first portion 640. The opposing surfaces that form the engagement mechanism 646 are parallel to one another to facilitate engagement of parallel surfaces on the jaws of a tool that is capable of subsequently rotating the first portion 640.

[0132] The tuning block 648 is mounted to the spacer 652A at a fixed location. The wafer chuck 72 includes a metal portion 682 and a protective tab 684. The protective tab 684 forms a shoulder 686 on the wafer chuck 72. Spacers 652B are located between the spacer 652A and the signal distribution board 500. Only a single spacer 652B is shown. Additional spacers are typically inserted on top of one another until the leveling surface 690 of the tuning block 648 is at the same vertical height as the shoulder 686.

[0133] The snap mechanism 654 includes a retainer body 694, a spherical ball 696, and a spring 698. The body 666 of the second portion 642 forms a portion of the snap mechanism 654 because the body 666 has a first snap recess 700A formed therein.

[0134] The retainer body 694 has an outer surface with threads 702 thereon. The retainer body 694 also has an end with a slot 704 formed therein that is capable of receiving a tool such as a screwdriver. The spring 698 is located within the retainer body 694. The spherical ball 696 is positioned within a mouth of the retainer body 694. The mouth of the retainer body 694 has a slightly reduced size to prevent the spherical ball 696 from falling out of the retainer body 694. An outer surface of the spherical ball 696 forms a snap surface 706. The threads 702 engage with complementary threads within the tuning block 648. A tool such as a screwdriver is inserted into the slot 704 and then rotated to adjust how far apart the snap surface 706 is from the tuning block 648.

[0135] The intermediate protection member 708 is inserted into a complementary recess on the upper surface of the back plate 74. Openings 710, 712, and 714 are formed in the intermediate protection member 708, the back plate 74, and the signal distribution board 500, respectively. The second portion 680 of the connection portion 644 is inserted through the openings 710, 712, and 714 from above. The length 660 of the first portion 640 is greater than the length of any of the openings 710, 712, and 714 in the same direction, which prevents the first portion 640 from entering the openings 710, 712, and 714. The lower surface of the first portion 640 rests on the upper surface formed within the intermediate protection member 708. The first portion 678 of the connection portion 644 is then located within the openings 710, 712, and 714, and the second portion 680 of the connection portion 644 is located below the openings 710, 712, and 714. The spring-loaded washer 720, the washer 652B, and the spacer 652A are then positioned on the connection portion 644 from below. The second portion 642 is then positioned on the connection portion 644 from below. The opening 674 forms a sliding fit with the outer diameter of the threads on the second portion 680 of the connection portion 644.

[0136] As the second portion 642 is slid upward on the connection portion 644, the first catch recess 700A also comes into contact with the catch surface 706. The spherical ball 696 moves a small amount from right to left against the spring force of the spring 698. The locking nut 650 then engages the protruding end of the second portion 680. Rotation of the locking nut 650 causes the body 666 of the second portion 642 to tighten against the spring force of the washer 720. A feeler gauge or other instrument can be used to determine the gap between the second tab 668B and the leveling surface 690. The locking nut 650 can be rotated until an acceptable gap is formed between the second tab 668B and the leveling surface 690. This gap is typically the same as the desired gap between the first tab 668A and the shoulder 686.

[0137] As the locking nut 650 is rotated, the first catch recess 700A also moves upward. The first catch recess 700A is an elongated slot. As the second portion 642 continues to move upward with continued rotation of the locking nut 650, the catch surface 706 and the first catch recess 700A can thus slide over one another.

[0138] As shown, when the first latch assembly 604A is assembled, the wafer chuck 72 is in place. Additionally, there is a negative pressure in the differential pressure cavity 622. By having the first wafer test module 28A in a compressed state, it is possible to measure whether the first and second fins 668A and 668B are spaced apart from the shoulder 686 and the leveling surface 690, among others. As long as the leveling surface 690 has been set at the correct height using one or more shims, such as the shim 652B, it is also possible to assemble the first latch assembly 604A into place without the wafer chuck 72 by simply measuring the spacing between the second fin 668B and the leveling surface 690.

[0139] Figure 16 is a view along the direction A in Figure 15 but only the connection 644 and the signal distribution board 500 are shown.

[0140] The opening 712 has a first dimension 724 in an axis 726 toward the center point of the signal distribution board 500 that is larger than a second dimension 728 that is transverse to the axis 726. The first portion 678 of the connection 644 is smaller than the first dimension 724 in the direction of the axis 726 to allow for thermal expansion of the signal distribution board 500 and the backplane 74 (see Figure 15 ) relative to each other. The first portion 678 is sized to fit slidably within the second dimension 728 to prevent the signal distribution board 500 from moving relative to the backplane 74 in a direction transverse to the axis 726.

[0141] The second portion 680 of the connection 644 has a first thickness 730 and a second thickness 732. The first thickness 730 can fit through the opening 712 in the direction of the axis 726 and the first thickness 730 is larger than the second dimension 728 of the opening 712. The second thickness 732 is transverse to the first thickness 730 and can fit through the second dimension 728 of the opening 712. Because the second dimension 728 is relatively large, it allows for threads to be formed thereon and it is still relatively strong. The entire second portion 680 is below the opening 712, which allows the connection 644 to rotate about its longitudinal axis without the second portion 680 getting stuck on the relatively narrow opening 712. The first portion 678 has a circular cross-section with a diameter that is no larger than the second dimension 728, which allows the first portion 678 to rotate freely within the relatively narrow second dimension 728 of the opening 712.

[0142] An additional opening 734 is formed in the signal distribution board 500 for additional securing of shims. The opening 734 is similarly proportioned to the opening 712 with a longer dimension in an axis 736 toward the center point of the signal distribution board 500. When used in a manufacturing environment, the anchor that passes through the opening 734 does not have to rotate and the dimensions of the opening 734 are only for allowing thermal expansion of the signal distribution board 500 relative to the backplane 74.

[0143] Figure 17 for Figure 15 Cross-sectional view of section 17-17, with retainer 740 inserted through. Figure 16 The opening 734 is used to secure the spacer 652A and the gasket 652B to the back plate 74. The retainer 740 includes a bolt and a nut, wherein the head of the bolt is on one side and the nut is on the opposite side.

[0144] The main body 666 has a circular outer surface 742 in which first, second, third, and fourth snap-fit ​​recesses 700A to 700D are formed. The snap-fit ​​surface 706 of the spherical sphere 696 is located within the first snap-fit ​​recess 700A, which prevents the main body 666 from rotating. An opening 674 within the main body 666 is keyed to receive the shape of the second portion 680, such that if the main body 666 remains stationary, the second portion 680 cannot rotate.

[0145] A small amount of torque is required to rotate the main body 666 and dislodge the spherical ball 696 from the first snap-fit ​​recess 700A. If the main body 666 rotates clockwise, the snap-fit ​​surface 706 rests on the circular outer surface 742 between the first snap-fit ​​recess 700A and the second snap-fit ​​recess 700B. As the main body 666 rotates, the second part 680 rotates with the main body 666 by the same angle. When the main body 666 has rotated approximately 90 degrees, the snap-fit ​​surface 706 snaps into the second snap-fit ​​recess 700B. The second snap-fit ​​recess 700B then prevents the rotation of the main body 666 and the second part 680. The first to fourth snap-fit ​​recesses 700A to 700D gently lock the main body 666 at four different rotation angles, including 0 degrees, 90 degrees, 180 degrees, and 270 degrees.

[0146] Figure 18A(i) and 18A(ii) It is along Figure 15 The view is in the direction of arrows A and B, but the locking mechanism is rotated to the unlocked position. The operator can compare the orientation of the first part 640 with the reference 750 on the upper surface of the wafer chuck 72. In Figure 18A(ii), the first latch assembly 604A is shown unlocked. The shoulder 686 is not obstructed from below by either the first flap 668A or the second flap 668B. Flaps 668A and 668B are... Figure 15 and 17 The latching mechanism 654 shown is held in the position indicated in Figure 18A(i). The pressure within the first wafer test module 28A can be reduced, and the wafer chuck 72 can be removed to insert or replace a wafer. After the wafer is replaced, the pressure within the first wafer test module 28A is reduced again to hold the first wafer test module 28A together.

[0147] When the first wafer test module 28A is fully assembled, it can be desirable to provide further fail-safe protection so that electrical contact with the wafer is maintained even if negative pressure within the first wafer test module 28A cannot be maintained due to a system failure. An operator can use a tool (not shown) having jaws and a probe. The probe is inserted into the tool probe hole 664. The tool probe hole 664 is tapered so that the deeper the probe is inserted into the tool probe hole 664, the more the tool becomes aligned with the first portion 640. The operator then engages the opposing parallel surfaces of the jaws of the tool with the opposing parallel surfaces formed by the engagement mechanism 646. Once the tool is engaged with the engagement mechanism 646, the operator rotates the tool and the tool rotates the first portion 640. The connecting portion 644 and the second portion 642 and their first and second wings 668A and 668B rotate with the first portion 640. Referring to Figure 17 The catch surface 706 exits the fourth catch recess 700D and slides on the circular outer surface 742. Then, the catch surface 706 catches into the first catch recess 700A.

[0148] Figure 18B(i) and 18B(ii) A first latching assembly is shown after the first portion 640 and the second portion 642 are rotated through an angle of 90 degrees. The operator can see that the orientation of the first portion 640 matches the locked position shown by reference numeral 750. The first wing 668A is now above the shoulder 686, which prevents movement of the wafer chuck 72 in a vertically downward direction away from the rest of the wafer test module 28A. The second wing 668B is located on the tuning block 648. The first wing 668A can be disengaged from the shoulder 686 by rotating the first portion 640 through 90 degrees either clockwise or counterclockwise. Either of the wings 668A or 668B can be used to lock the wafer chuck 72 in place.

[0149] Figure 19 One or more spacers 652B through 652F are shown as being used to adjust the height of the leveling surface 690 of the tuning block 648. Ideally, the tuning block 648 should be at the same height as the shoulder 686. Since the tuning block 648 is mounted to the spacer 652A, as more spacers 652B through 652F are inserted, the tuning block 648 moves up and down with the spacer 652A. If the leveling surface 690 is below the shoulder 686, more spacers can be inserted to raise the leveling surface 690, or if the leveling surface 690 is above the height of the shoulder 686, spacers can be removed.

[0150] The engagement mechanism 646 is conveniently located directly on the first portion 640. In another arrangement, the engagement mechanism can be formed directly on the second portion 642 or directly on the connecting portion 644.

[0151] In another embodiment, the engagement mechanism can be a mechanism separate from the first and second portions 640, 642 and from the connecting portion 644. For example, a worm gear can be formed on the connecting portion 644 and the engagement mechanism can be a separate rotatable mechanism that rotates the worm gear.

[0152] The engagement mechanism can also be located between the first portion 640 and the connecting portion 644. For example, the first flap 668A can pivot downward away from the shoulder 686 and pivot rearward toward the shoulder 686 with a cam system located between the first portion 640 and the connecting portion 644. This cam system as an engagement mechanism can alternatively be located between the connecting portion 644 and the second portion 642. Or, the connecting portion 644 can be made in two pieces and the engagement mechanism can connect and adjust the spacing of the two pieces and the spacing adjustment can pivot the flap.

[0153] The first latch assembly 604A is primarily made using non-compressible and non-flexible materials. In alternative embodiments, a belt or other flexible material can be used for the same or similar purposes.

[0154] Instead of having the engagement mechanism 646 on the outer surface of the first portion 640, the engagement mechanism can instead be on the inner surface of any of the portions.

[0155] Referring again to Figure 12 , the first, second, third, and fourth latch assemblies 604A-D are identical except for their respective locations and orientations. The first and third latch assemblies 604A and 6040C are located on opposite sides of the wafer chuck 72 and the second and fourth latch assemblies 604B and 604D are located on opposite sides of the wafer chuck 72. Because the latch assemblies 604A-D are located on more than one side of the wafer chuck 72, i.e., they cover more than 180 degrees around the circumference of the wafer chuck 72, they can collectively hold all sides of the wafer chuck 72 in place around its entire circumference.

[0156] The latch system provided by the first, second, third, and fourth latch assemblies 604A-D facilitates easier movement of the first wafer test module 28A in a manufacturing environment without the need for human supervision. Without the latch system, human supervision would be required to determine when the negative pressure within the first wafer test module 28A fails and when the wafer 28A separates. The latch system provides a failsafe mechanism to prevent the first wafer test module 28A from separating even if it is drawing air from the outside.

[0157] Figure 20 、 21 , 22A and 22B show other components of the pressure monitoring system, including pressure sensing channels 760 Figure 21 ), pressure sensors 762 Figure 22A and 22B), reference Figure 11 The electronic pressure sensor interface 606 ( Figure 20 , 21 768 (22A and 22B), electronic pressure connector interface 764, mounting bracket 766, and ribbon cable 768 having first and second connectors 770 and 772 at their opposite ends. Figure 20 , 22A and 22B), connector block 774 and reinforcing plate 776 ( Figure 20 ).

[0158] Pressure sensing channel 760 is similar to a reference Figure 13 The pressure relief channel 608 is formed in the back plate 74. The pressure sensing channel 760 has Figure 14 The first end is located within the differential pressure chamber 622 shown. The pressure sensing channel 760 has a second end opposite to the first end near the outer edge of the back plate 74.

[0159] The electronic pressure sensor interface 606 is in the form of a printed circuit board, which has a substrate 780 and multiple contacts, including first, second and third contacts 782A, 782B and 782C formed on the substrate 780.

[0160] Pressure sensor 762 is mounted to substrate 780 on the side opposite to the first, second, and third contacts 782A, 782B, and 782C. Pressure sensor 762 is electrically connected to the first, second, and third contacts 782A, 782B, and 782C via substrate 780. Pressure sensor 762 is capable of sensing the pressure of a gas (in this case, air) and converting the pressure into an electrical signal, wherein the magnitude of the pressure is indicated by the magnitude of the signal or another variable. Pressure can be conveniently detected using a diaphragm that displaces a known distance as pressure increases or decreases. Other pressure sensors are also within the scope of this invention, such as pressure sensors using piezoelectric crystals or pressure sensors using stress meters. In the case of moving the diaphragm, for example by moving an induction coil, the movement can be converted into a voltage, and the magnitude of the voltage then indicates the displacement and thus the pressure. The pressure sensor can be, for example, the MLX90809 sold by Melexis (www.melexis.com). The electronic pressure sensor interface 606 is mounted to backplate 74 using fastener 784. The diaphragm of the pressure sensor 762 is then exposed to air at the second end of the pressure sensing channel 760. The pressure sensor 762 can therefore sense the pressure within the differential pressure chamber 622.

[0161] The electronic pressure connector interface 764 has a plate 790 and a plurality of terminals, including first through sixth terminals 792A-792F secured to the plate 790. The plate 790 is mounted to the mounting bracket 766 by fasteners 794. The reinforcement plate 776 is secured between the two pusher blade 308. The mounting bracket 766 is secured to the reinforcement plate 776 by fasteners 796. The slot assembly body 32 forms part of the fixture structure along with the pusher blade 308 and the reinforcement plate 776, and the electronic pressure connector interface 764 is thus mounted to the fixture structure.

[0162] The connector block 774 is mounted to the slot assembly body 32. Connectors 770 and 772 are connected to the electronic pressure connector interface 764 and the connector block 774, respectively. The first through sixth terminals 792A-792F are connected to a pressure sensing board of the electronic tester through the first connector 770, the ribbon cable 768, and the second connector 772.

[0163] Figure 23A And 23B The engagement of the electronic pressure sensor interface 606 with the electronic pressure connector interface 764 when the first wafer test module 28A is inserted into the slot assembly is shown. The first, second, and third contacts 782A, 782B, and 782C first come into contact with the first, second, and third terminals 792A, 792B, and 792C, respectively. Further movement of the electronic pressure sensor interface 606 causes the first, second, and third contacts 782A, 782B, and 782C to engage the fourth, fifth, and sixth terminals 792D, 792E, and 792F, respectively. The first contact 782A thus comes into contact with both the first terminal 792A and the fourth terminal 792D. Similarly, each of the contacts 782B and 782C comes into contact with two of the terminals 792B, 792C, 792E, and 792F.

[0164] The terminals 792A-792F can be resiliently pressed against the plate 790 to ensure proper contact with the contacts 782A-782C. The ribbon cable 768 allows for a small amount of movement of the reinforcement plate 776 relative to the slot assembly body 32 upon insertion of the first wafer test module 28A.

[0165] The pressure within the differential pressure cavity 622 can be monitored throughout the process while the wafer is under test. If the wafer test fails, the tester can be programmed to determine if such a test failure can be the result of a negative pressure failure within the differential pressure cavity 622.

[0166] Figure 24 Further components of the test apparatus 10 and slot assemblies 18A and 18B are shown. Figure 24Additional components found within the manufacturing environment are also shown, including a nitrogen gas tank 802, a dielectric gas tank 804, and a vacuum pump 806. The nitrogen gas tank 802 and the vacuum pump 806 can be backup equipment for nitrogen gas lines and vacuum lines that can be found in the manufacturing environment.

[0167] The test set 10 includes a first nitrogen gas pressure regulator 810 and three manifolds 812, 814, and 816. The slot assembly 18A has three couplers 820A, 822A, and 824A. Similarly, the slot assembly 18B has three couplers 820B, 822B, and 824B.

[0168] In use, when the slot assembly 18A is inserted into the test set 10, the couplers 820A, 822A, and 824A connect to the manifolds 812, 814, and 816. When the slot assembly 18B is inserted into the test set 10, the couplers 820B, 822B, and 824B simultaneously engage with the manifolds 812, 814, and 816. The couplers 820A and 820B connect the slot assemblies 18A and 18B to the nitrogen gas pressure regulator 810 through the manifold 814. The first nitrogen gas pressure regulator 810 connects to the nitrogen gas tank 802 through a nitrogen gas supply inlet. The couplers 822A and 822B connect the slot assemblies 18A and 18B through the manifold 814 and a dielectric gas supply inlet of the dielectric gas tank 804. The couplers 824A and 824B connect the slot assemblies 18A and 18B to the vacuum pump 806 through the manifold 816, which provides a vacuum to the manifold 816.

[0169] The slot assemblies 18A and 18B are similar. For discussion purposes, only the other components of the slot assembly 18A are discussed, but it should be understood that the slot assembly 18B has similar components.

[0170] The slot assembly 18A also includes a second nitrogen gas pressure regulator 830, a dielectric gas pressure regulator 834, an inlet aperture 838, an outlet aperture 840, a vacuum regulator 844, and a heating control board 848. The second nitrogen gas pressure regulator 830 and the dielectric gas pressure regulator 834 are connected to the couplers 820A and 822A, respectively. The inlet aperture 838 is connected to the second nitrogen gas pressure regulator 830 and the dielectric gas pressure regulator 834.

[0171] The first wafer test module 28A has a gas supply valve 850 connected to the inlet aperture 838. The gas supply valve 850 is similar to the vacuum release check valve 602, except that it operates at a different pressure. A gas supply passage 852 has an inlet connected to the gas supply valve 850 and an outlet at the differential pressure chamber 622 shown. Figure 14

[0172] ​The outlet port 840 is connected to the pressure reducing check valve 600. The outlet port 840 is connected to the connector 824A via the vacuum regulator 844.

[0173] The heating control board 848 is connected to the voltage pressure sensor interface 606, and also to the second nitrogen pressure regulator 830, the dielectric gas pressure regulator 834, and the vacuum regulator 844. The heating control board 848 controls the second nitrogen pressure regulator 830, the dielectric gas pressure regulator 834, and the vacuum regulator 844 based on inputs from the voltage pressure sensor interface 606.

[0174] In operation, the heating control panel 848 opens the vacuum regulator 844. Then, the vacuum generated by the vacuum pump 806 is connected to and opens the pressure-reducing check valve 600. The heating control panel 848 keeps the dielectric gas pressure regulator 834 closed. The heating control panel 848 opens the second nitrogen pressure regulator 830. Nitrogen then flows from the nitrogen tank 802 through the nitrogen supply inlet, nitrogen pressure regulator 810, manifold 812, connector 820A, second nitrogen pressure regulator 830, inlet orifice 838, gas supply valve 850, and gas supply passage 852 into the differential pressure chamber 622. The differential pressure chamber 622 is then filled with nitrogen, and all air in the differential pressure chamber 622 is discharged through the pressure-reducing check valve 600, outlet orifice 840, vacuum regulator 844, connector 824A, and vacuum pump 806. See also... Figure 8B Then, nitrogen gas is used to fill the space between the front contacts 562 of the contact plate.

[0175] Refer again Figure 8B The heating control panel 848 then closes the second nitrogen pressure regulator 830 and opens the dielectric gas pressure regulator 834. The dielectric gas then flows from the dielectric gas tank 804 through the dielectric gas supply inlet, manifold 814, connector 822A, dielectric gas pressure regulator 834, inlet orifice 838, gas supply valve 850, gas supply channel 852, differential pressure chamber 622, pressure reducing check valve 600, outlet orifice 840, vacuum regulator 844, connector 824A, and vacuum pump 806. Arrow 858 indicates the flow direction of the dielectric gas through the differential pressure chamber 622. The flow rate of the dielectric gas is controlled by the dimensions of the inlet orifice 838 and outlet orifice 840.

[0176] once Figure 8B The space between the contacts 562 at the front end of the contact plate is filled with dielectric gas. The heating control board 848 partially shuts off the dielectric gas pressure regulator 834 and the vacuum regulator 844 to reduce the flow rate of the dielectric gas. The flow rate of the dielectric gas is low, and only compensation is needed for leakage of the dielectric gas from the differential pressure chamber 622. Throughout the process of introducing nitrogen and dielectric gas into the differential pressure chamber 622, the heating control board 848 controls the vacuum regulator 844 in a certain way to maintain compression.Figure 8A The negative pressure is created by the helical spring 544 in the middle.

[0177] When compared to air, dielectric gases are chosen to reduce [the following] Figure 8B The arc between contacts 562 at the front end of the contact plate. The gas that can be used as the dielectric can be, for example, a gas sold by 3M. 4710 is an insulating gas, or commercially available octafluorocyclobutane. Both gases have a higher dielectric constant and dielectric strength than air, thus reducing arcing compared to air. When testing... Figure 25 When the first wafer 32A is in the test chamber, additional power can be provided through the contact point 562 at the front end of the contact plate. After testing is completed, the dielectric gas is replaced with nitrogen following the reverse process described above, which allows the first wafer test module 28A to be removed from the slot assembly 18A. Throughout the process, excess nitrogen and excess dielectric gas are removed from the first wafer test module 28A through the exit orifice 840, vacuum regulator 844, connector 824A, and vacuum pump 806. One manufacturing apparatus may have a scrubber that separates the gas after it leaves the vacuum pump 806. Another manufacturing apparatus may have a cryogenic pump that separates the gas after it leaves the test apparatus 10 and before it enters the vacuum pump 806.

[0178] As described above, each slot assembly 18A, 18B, etc., has its own heating control board 848 and other similar components. The heating control board 848 independently controls the introduction of nitrogen and dielectric gas into the contacts of the corresponding first wafer test module 28A, second wafer test module 28B, etc.

[0179] Figure 26 This is a top view of the slot assembly 18A while the first wafer test module 28A is in place. Figure 25 yes Figure 27 Sectional views of 26A-26B. Figure 25 yes Figure 28 Sectional views of 27A-27B.

[0180] Figure 26 and 29 They are Figure 28 and 27 Detailed views of the areas marked "C" and "D". Figure 28 The diagram shows a horizontal conveyor 304, a pusher blade 308, and a back plate 74, wherein a pressure-reducing channel 608 is formed within the back plate 74. Figure 1 A degassing duct 828 is also shown, which is fixed to the horizontal conveying device 304. The degassing duct 828 has a fixed degassing interface 832. The back plate 74 has a movable degassing interface 836.

[0181] In use, the fixed structure degas interface 832 and the movable structure degas interface 836 are separated from each other. As described with reference to Figure 24 the wafer chuck 72 is moved downward into contact with the hot chuck 34. The fixed structure degas interface 832 is moved downward and into engagement with the movable structure degas interface 836. A seal seals the fixed structure degas interface 832 and the movable structure degas interface 836. The reduced pressure passageway 608 then extends from the back plate 74 through the degas tube 828. Figure 29 and 28 The vacuum shown in FIG. 8 can be applied to the reduced pressure passageway 608 through the degas tube 828.

[0182] Figure 1 The horizontal transport 304, the pusher blade 308, and the back plate 74 are shown with a gas supply passageway 852 formed within the back plate 74. A gas supply tube 826 is mounted to the horizontal transport 304. The gas supply tube 826 has a fixed structure gas supply interface 842. The back plate 74 has a movable structure gas supply interface 846. The fixed structure gas supply interface 842 is initially separated from the movable structure gas supply interface 846. When the wafer chuck 72 is moved downward into contact with the hot chuck 34 in FIG. 7, the movable structure gas supply interface 846 is moved downward into contact with the fixed structure gas supply interface 842. A seal seals the movable structure gas supply interface 846 to the fixed structure gas supply interface 842. The gas supply passageway 852 then extends through the horizontal transport 304, the gas supply tube 826, into and through the back plate 74. As shown in FIG. 8, nitrogen and dielectric pressurized gas is provided through the gas supply tube 826 and the back plate 74 to the area between the contacts. After the test is completed, the back plate 74 is separated from the degas tube 828 shown in FIG. 7 and the gas supply tube 826 shown in FIG. 8. Figure 24 Figure 28 Figure 29 Figure 30

[0183] Figure 29 The gas box 860 connects the couplers 820A, 822A, and 824A to the gas supply tube 826 shown in FIG. 7 and the degas tube 828 shown in FIG. 8. Figure 28 Figure 31

[0184] As shown in FIG. 9, the gas box 860 is connected to the gas supply tube 826 and the degas tube 828. The gas box 860 is connected to the gas supply tube 826 and the degas tube 828. Figure 24 and 32 ​​​​​​As shown, gas cassette 860 includes a base 862, an intermediate substrate 864, a channel block 866, a turn block 868, a mounting plate 870, various regulators including a second nitrogen pressure regulator 830, a dielectric gas pressure regulator 834, a vacuum regulator 844, and various connectors including a vacuum receiving connector 872, a nitrogen receiving connector 874, a dielectric gas receiving connector 876, a vacuum supply connector 880, a gas supply connector 882, a valve control connector 884, and releasable interfaces 892 and a cover 896.

[0185] Vacuum receiving connector 872, nitrogen receiving connector 874, and dielectric gas receiving connector 876 are affixed to the front of base 862. Base 862 has channels (not shown) formed therein that extend from connectors 872, 874, and 876 to three releasable interfaces 892. Vacuum supply connector 880 and gas supply connector 882 are affixed to a side of base 862. More channels within base 862 connect connectors 880 and 882 to two or more releasable interfaces 892. Connectors 872, 874, 876, 880, and 882 are generally in the same plane.

[0186] Turn block 868 and channel block 866 are mounted to intermediate substrate 864. Releasable intermediate substrate 864 has three releasable interfaces (not shown) that are spaced the same distance apart as releasable interfaces 892 connected to connectors 872, 874, and 876. Channel block 866 has two releasable interfaces (not shown) that are spaced the same distance apart as releasable interfaces 892 connected to connectors 880 and 882. When intermediate substrate 864 is mounted on base 862, the releasable interfaces of intermediate substrate 864 mate with releasable interfaces 892 of base 862. Channels are formed through intermediate substrate 864, turn block 868, and channel block 866. Turn block 868 thus connects connectors 872, 874, and 878 to channel block 866. Turn block 868 also transforms gas flow from being horizontally parallel in a first direction 890 to being vertically parallel in a second direction 894 at a right angle to first direction 890.

[0187] Regulators 830, 834, 844 are mounted on channel block 866. Regulators 830, 834, and 844 can individually regulate the various gases through channel block 866. After leaving regulators 830 and 834, channel block 866 merges the channels leading from regulators 830 and 834 before passing through one of the releasable interfaces 892 in base 862 to gas supply connector 882.

[0188] A mounting plate 870 is affixed to one side of the intermediate substrate 864. A valve control connector 884 is affixed to the mounting plate 870. The valve control connector 884 is electrically connected to the electrical terminals on the regulators 830, 834, and 844.

[0189] A cover 896 is shaped to fit over the channel block 866, the turn block 868, the mounting plate 870, and the intermediate substrate 864. Slots in the sides of the cover 896 allow the valve control connector 884 to protrude outwardly to the cover 896.

[0190] In use, the gas supply connector 882 is connected with the inlet port 838 in Figure 24 and the vacuum supply connector 880 is connected with the outlet port 840 shown in Figure 24 . The valve control connector 884 is connected with the heating control board 848 shown in Figure 30 . The dielectric gas receiving connector 876, the nitrogen receiving connector 874, and the vacuum receiving connector 872 are also connected with the couplers 822A, 820A, and 824A, respectively.

[0191] Signals are provided through the valve control connector 884 to the regulators 830, 834, and 844 to control the flow of gas and vacuum to the gas supply connector 882 and the vacuum supply connector 880. For example, if nitrogen is introduced, the vacuum regulator 844 is opened to introduce a vacuum through the vacuum receiving connector 872 to the vacuum supply connector 880, and the dielectric gas pressure regulator 830 is opened to connect the dielectric gas receiving connector 876 to the gas supply connector 882.

[0192] The gas box 860 provides a serviceable form factor for the regulators 830, 834, and 844. The intermediate substrate 864 can be released from the base 862, so the base 862 can remain mounted to the remainder of the slot assembly 18A in Figure 33 while the regulators 830, 834, and 844 or the valve control connector 884 are serviced. The releasable interface 892 allows a vertical connection between the intermediate substrate 864 and the base 862, with all of the gas lines and vacuum lines connected simultaneously in a single, simple operation. Thus, there is no need to disconnect the lines from the connectors 872 to 882.

[0193] Figure 8AOther aspects of the test apparatus are shown. Certain components have been described with reference to the previous figures. For example, components of the slot assembly 18A include the hot chuck 34, the hot fluid channel 224, the connection plate 66, and the first slot assembly interface 40. Components of the first wafer test module 28A that have been described include the signal distribution board 500, the stiffener plate 776, the contact plate 502, the wafer contact probes 504, the contact plate front end contacts 562, the wafer test module interface 78, and the wafer chuck 72. As previously described, the contact plate front end contacts 562 are located on the tips of the wafer contact probes 504. Some of the contact plate front end contacts 562 are power contact plate front end contacts that provide power to selected ones of the terminals 588 (see Figure 28 and 8B ) of the wafer 32A. During testing, the power contact plate front end contacts provide power to the wafer 32A. During testing, others of the contact plate front end contacts 562 provide signals to and receive signals from the wafer 32A.

[0194] Other components of the test apparatus include the tray 900, the ground reflow probes 902, the wafer chuck probes 908, and the vacuum tubing 910.

[0195] The tray 900 includes a substrate 912 of dielectric material and a conductive layer 914 formed on the substrate 912. The conductive layer 914 has conductive portions 916 and reflow terminal regions 918. The conductive portions 916 and the reflow terminal regions 918 have exposed upper surfaces 920. The wafer 32A has terminals that form part of the circuit in the wafer 32A and are located on the underside of the wafer 32A. The terminals located on the underside of the wafer 32A are in contact with the exposed upper surfaces 920 of the conductive portions 916. The conductive layer 914 can then be used to provide a reference voltage, such as a ground voltage, to the terminals on the underside of the wafer 32A.

[0196] The ground reflow probes 902 are mounted on the contact plate 502. The lower end of each ground reflow probe 902 forms a ground reflow contact 922. The ground reflow probes 902 extend beyond the edges of the wafer 32A so that the ground reflow contacts 922 are in contact with the reflow terminal regions 918. The ground reflow probes 902 form electrical conductors that connect the conductive layer 914 to the signal distribution board 500. The electrical conductors extend through the signal distribution board 500, the wafer test module interface 78, the first slot assembly interface 40, the connection plate 66 to the tester electronics described previously with reference to the figures. The tester electronics can then provide a reference voltage, such as ground, to the terminals on the underside of the wafer 32A.

[0197] Wafer chuck probes 908 are mounted to the contact plate 502. Each wafer chuck probe 908 extends under the contact plate 502 through the wafer 32A and the tray 900, and has a lower tip that contacts the wafer chuck 72. The ground reference voltage is then provided to the wafer chuck 72 through the signal distribution plate 500 and the wafer chuck probes 908. By grounding the wafer chuck 72, the wafer chuck 72 is held at a known voltage, which allows for control of electrical arcing between various conductive components, such as between the terminals on the underside of the wafer 32A and the wafer chuck 72.

[0198] When testing of the wafer 32A is complete, the wafer 32A can be removed from the tray 900 and the tray 900 can remain on the wafer chuck 72. Alternatively, after testing is complete, the tray 900 carrying the wafer 32A is removed from the wafer chuck 72, and the tray 900 can provide structural rigidity for very thin wafers. In either case, the tray 900 and the wafer chuck 72 collectively form a wafer holder 924 for the wafer 32A when the wafer 32A is being tested.

[0199] A plurality of vacuum openings 926 are formed through the tray 900 and partially through the wafer chuck 72. Vacuum channels 928 in the wafer chuck 72 connect the lower ends of the vacuum openings 926 to each other. The vacuum piping 910 also defines a vacuum channel, and is connected to the vacuum channels 928 in the wafer chuck 72. The vacuum piping 910 can use, for example, a vacuum tube, a vacuum hose, or a vacuum line. Figure 11 The interfaces 832 and 836 shown are connected to the vacuum channels 928.

[0200] In use, a vacuum is provided to the vacuum openings 926 through the vacuum piping 910 and the vacuum channels 928. Because the vacuum openings 926 are open at the top, the lower surface of the wafer 32A is exposed to the vacuum. When the vacuum is applied, the vacuum secures the wafer 32A to the tray 900. The vacuum can be applied to secure the wafer 32A to the tray 900 when the first wafer test module 28A is assembled and before the first wafer test module 28A is inserted into the slot assembly 18A. The vacuum can be applied using a vacuum pump 806 shown in Figure 28 The same pressure reducing check valve 600 and vacuum release check valve 602 shown for holding the first wafer test module 28A closed are used to hold the vacuum. When the first wafer test module 28A is inserted into the slot assembly 18A, the vacuum can be released through Figure 24 the interfaces 832 and 836 in and the vacuum pump 806 shown in Figure 34 are used to hold the vacuum.

[0201] Figure 33 is Figure 33An enlarged view of detail "E". The vacuum opening 926 includes a proximal portion 932, a distal portion 934, and an enlarged portion 936. The proximal portion 932 has a relatively small diameter and extends through the tray 900. The enlarged portion 936 is formed in the upper surface of the wafer chuck 72 and has a much larger diameter than the proximal portion 932. The distal portion 934 is formed by the bottom of the enlarged portion 936 and extends into the vacuum opening 926 as shown. Figure 35 The distal portion 934 has a much smaller diameter than the enlarged portion 936.

[0202] By varying the diameter of the vacuum opening 926 from the inlet opening 940 to the outlet opening 942, the likelihood of arcing between the conductive layer 914 and the wafer chuck 72 can be reduced in the event that the conductive layer 914 and the wafer chuck 72 are at different voltages. The large diameter of the enlarged portion 936 creates a larger distance such that an arc must pass between the conductive layers 914 through the inlet opening 940, through the proximal portion 932, and through the space within the enlarged portion 936 before reaching the conductive metal material of the wafer chuck 72. In addition, an electrical insulator 944 is formed around the inlet opening 940 to further separate the metal of the conductive layer 914 from the inlet opening 940.

[0203] The vacuum provided through the vacuum opening 926 is also used to hold the tray 900 against the wafer chuck 72. A chamfer 948 is formed around the upper periphery of the enlarged portion 936 for deburring purposes and to ensure flush contact between the lower surface of the tray 900 and the upper surface of the wafer chuck 72. Figure 14 and 36 are right angle cross sections of the wafer chuck 72 and the tray 900. The figures show the relative positioning of the tray 900 and the groove 950 for the lip seal 77, which will be described in more detail with reference to ​

[0204] While certain example implementations have been described herein, it should be understood that many variations and modifications of the systems and processes described herein can be made and that such changes and modifications can be made to the example without departing from the spirit and the scope of this application. Therefore, regardless of the content of any section entitled "Summary" or any similar section, no such entitled section or any other section, nor any summary or abstract if any, taken alone or in combination with other sections of this detailed description, is to be used to construe the application nor should such a section or sections be used in interpreting the scope of the claims in such claims are self-defining.​

Claims

1. A test apparatus comprising: a tray for releasably holding a wafer, wherein the tray has at least a portion that is electrically conductive and has an exposed surface to contact back wafer terminals on a back side of the wafer; a contact plate; contact plate front end contacts mounted to the contact plate, each contact plate front end contact having a surface positioned to contact a corresponding front wafer terminal on a front side of the wafer; an electronic tester connected to the contact plate front end contacts so that, in use, electrical current is conducted between the electronic tester and circuitry in the wafer through the front side wafer contacts and the contact plate front end contacts to test the circuitry; and an electrical conductor connecting the electrically conductive portion so that, in use, the circuitry is connected to the electronic tester through the back wafer contacts, the exposed surface of the electrically conductive portion, and an electrically conductive path. a hot chuck, in use, the tray is thermally connected to the hot chuck and heat is transferred between the hot chuck and the wafer.

2. The test device of claim 1, further comprising: the hot chuck has a thermal passageway so that, in use, a fluid flows through the thermal passageway and heat is transferred between the fluid and the hot chuck.

3. The test device of claim 2, wherein, 4. The test apparatus of claim 1, further comprising: a wafer chuck on which the tray is positioned, the wafer chuck having a vacuum passageway therethrough, the tray having a plurality of vacuum openings therethrough, each vacuum opening connecting the back side of the wafer to the vacuum passageway in the wafer chuck so that when a vacuum is applied to the vacuum passageway, the vacuum secures the back side of the wafer to the tray. the tray includes:

5. The test device of claim 4, wherein, an electrical insulator surrounding an entrance opening of each vacuum opening.

6. The test apparatus of claim 4, further comprising: at least one wafer chuck probe mounted to the contact plate, the wafer chuck probe having a ground contact that contacts the wafer chuck. the wafer chuck probe extends beyond an edge of the tray.

7. The test device of claim 6, wherein, 8. The test apparatus of claim 6, further comprising a plurality of wafer chuck probes. the tray includes a reflow terminal area electrically connected to the exposed surface of the tray, and the contact plate front end contacts mounted to the contact plate are power contact plate front end contacts, and the electrical reflow conductor includes:

9. The test device of claim 1, wherein, a ground reflow contact mounted to the contact plate and having a surface positioned to contact the reflow terminal area on the tray.

10. The test apparatus of claim 9, further comprising: a plurality of wafer contact probes mounted to the contact plate, the power contact plate front end contacts being on the wafer contact probes; and at least one ground reflow probe mounted to the contact plate, the ground reflow contact being on the ground reflow probe. the ground reflow probe extends beyond an edge of the wafer.

11. The test device of claim 10, wherein, 12. The test apparatus of claim 10, further comprising a plurality of ground reflow probes. ​ 13. The test device of claim 9, further comprising: A signal distribution board, the signal distribution board comprising: A signal distribution board substrate; Signal distribution board contacts on the signal distribution board substrate; Signal distribution board terminals on the signal distribution board substrate; and Signal distribution board conductors connecting the signal distribution board contacts to the signal distribution board terminals.

14. The test apparatus of claim 13, further comprising: A reinforcement plate positioned to support the signal distribution board substrate.

15. A method of testing a wafer, comprising: Holding a wafer in a tray, wherein the tray has at least a portion that is electrically conductive and has an exposed surface to contact back wafer terminals on a back side of the wafer; Moving a contact plate and the tray toward each other so that surfaces of contact plate contacts mounted to the contact plate contact corresponding front wafer contacts on a front side of the wafer; Conducting electrical current between an electronic tester and circuitry in the wafer through the front side wafer contacts and the contact plate contacts to test the circuitry, The circuitry connected to the electronic tester through the back wafer terminals, the exposed surface of the electrically conductive portion, and the electrically conductive path; And Removing the wafer from the tray.

16. The method of claim 15, further comprising: Thermally connecting the tray to the thermal chuck; And Transferring heat between the thermal chuck and the wafer.

17. The method of claim 16, wherein, Fluid flows through a thermal channel of the thermal chuck, and heat is transferred between the fluid and the thermal chuck.

18. The method of claim 15, the tray positioned on a wafer chuck having a vacuum channel therethrough, the tray having a plurality of vacuum openings therethrough, each vacuum opening connecting a back side of the wafer to the vacuum channel in the wafer chuck, such that the method further comprises: Applying a vacuum to the vacuum channel, the vacuum securing the back side of the wafer to the tray.

19. The method of claim 18, wherein, The tray comprising: An electrical insulator surrounding an entrance opening of each vacuum opening.

20. The method of claim 18, further comprising: Forming a contact between a ground contact of at least one wafer chuck probe mounted to the contact plate and the wafer chuck.

21. The method of claim 20, wherein, The wafer chuck probe extending beyond an edge of the tray.

22. The method of claim 20, further comprising forming a contact between a plurality of wafer chuck probes mounted to the contact plate and the wafer chuck.

23. The method of claim 15, wherein, The tray comprising a reflow terminal area electrically connected to the exposed surface of the tray, and the contact plate front terminal contacts mounted to the contact plate are power contact plate front terminal contacts, and the electrical reflow conductors comprise: A ground reflow contact mounted to the contact plate and having a surface positioned to contact the reflow terminal area on the tray.

24. The method of claim 23, wherein: A plurality of wafer contact probes are mounted to the contact plate, the power contact plate front terminal contacts are on the wafer contact probes; And At least one ground return probe is mounted to the contact plate, the ground return contact being on the ground return probe.

25. The method of claim 24, wherein, The ground return probe extends beyond an edge of the wafer.

26. The method of claim 24, wherein, A plurality of ground return probes are mounted to the contact plate.

27. The method of claim 23, further comprising: The contact plate is connected to a signal distribution plate, the signal distribution plate comprising: a signal distribution plate substrate; a signal distribution plate contact on the signal distribution plate substrate; a signal distribution plate terminal on the signal distribution plate substrate; and a signal distribution plate conductor connecting the signal distribution plate contact to the signal distribution plate terminal.

28. The method of claim 27, further comprising: positioning a stiffener to support the signal distribution plate substrate.

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