Thermal Control in Test Systems

Abstract

The present invention discloses an exemplary test system, which includes a carrier having a test socket for receiving a device to be tested. The test socket includes an electrical connector. The test system also includes a cover assembly having a socket cover, which is used to contact the device to apply pressure to electrically connect the device to the electrical connector. The socket cover includes a material having a thermal conductivity exceeding a defined value. The cover assembly also includes one or more structures, which are configured to provide a surface area above which heat from the device is dissipated. The one or more structures are made of a material having a thermal conductivity exceeding a defined value.

Description

Technical Field

[0001] This specification generally relates to thermal control in test systems. Background Art

[0002] The test system is configured to test the operation of an electronic device, such as a microprocessor. Some types of electronic devices generate considerable heat during operation, including during testing. The generated heat, if not properly dissipated, may cause damage to the device, adversely affect test results, or both. Summary of the invention

[0003] An exemplary test system includes a carrier having a test socket for receiving a device to be tested. The test socket on the carrier includes an electrical connector. The test system also includes a cover assembly, which is composed of a socket cover, which is used to contact the device to apply pressure to electrically connect the device to the electrical connector. The socket cover includes a material having a thermal conductivity exceeding a defined value. The cover assembly also includes one or more structures, which are configured to provide a surface area above which heat from the device is dissipated. The one or more structures are composed of a material having a thermal conductivity exceeding a defined value. The exemplary test system may include one or more of the following features (alone or in combination).

[0004] One or more structures may include fins that are thermally connected to the device via the socket cover. The fins may extend away from the device. The fins may be arranged in one or more rows. The fins and the socket cover may be integrated into a single structure including a cover assembly. The fins may include or may be metal.

[0005] An exemplary test system may include a test slot for receiving a carrier. The test slot may include an interface to which the carrier is electrically connected. The test slot may include a blower configured to move air over the capping assembly. The carrier may include a second test socket for holding a second device to be tested.

[0006] An exemplary test system may include a thermal control chamber including air maintained at a certain temperature and a test rack for holding a test slot between a plurality of test slots. The test rack may include one or more blowers configured to move air into the thermal control chamber. The temperature may be ambient temperature.

[0007] An exemplary test system may include a test slot for receiving a carrier. The test slot may include an interface to which the carrier is electrically connected. The test system may include a robot for moving the carrier into and out of the test slot.

[0008] An exemplary test system may include an actuator configured to engage a socket cover to place or remove the socket cover over a device. The actuator may include: a key element that is rotatable; a tool ball that is disposed relative to the key element; and a block. The tool ball may be fixed to the block. The key element may pass through the block and may be movable relative to the block.

[0009] The socket cover may include a kinematic base. The kinematic base may include: a first structure including a groove configured and arranged to engage a tool ball, wherein the first structure has a hole, and wherein the hole and the key element have complementary shapes to allow the key element to pass through the hole; and a second structure having a hole, wherein the hole and the key element have complementary shapes to allow the key element to pass through the hole, and wherein the key element is configured to rotate to engage the second structure. The kinematic base may include at least one compression spring that can be controlled by the first structure and the second structure.

[0010] The actuator can be configured or operated to cause an operation including: the actuator engaging the socket cover, thereby forcing the tool ball against the groove and causing the key element to pass through the first structure and the second structure; the actuator rotating the key element; the key element is pulled against the second element while the tool ball is pushed against the groove to compress the compression spring; the actuator moves the socket cover into position above the device, thereby connecting the socket cover to the test carrier; and the actuator retracts after the socket cover is connected to the test carrier.

[0011] An exemplary test system includes: a cavity containing air maintained at a certain temperature; a test slot configured to receive air from the cavity, wherein the test slot includes at least one blower for moving air from the cavity through the test slot; and a carrier having a test socket for inserting into the test slot, wherein each test socket is configured to receive a device to be tested. The carrier includes a structure thermally connected to the device. The structure is used to provide a surface area over which heat from the device is dissipated. The structure includes a material having a thermal conductivity exceeding a defined value. At least one blower is configured to move air through the structure. The exemplary test system may include one or more of the following features (alone or in combination).

[0012] The structure may comprise fins extending away from the device. The fins may be arranged in one or more rows. The fins may comprise or be made of metal.

[0013] An exemplary test system may include a socket cover that fits over a device in a test socket. The structure and socket cover may be a single component including a capping assembly for a carrier. The test system may include a plurality of test slots. Each of the plurality of test slots may be configured to receive a separate carrier. Each carrier may be configured to hold one or more devices. The test system may include a control system that includes a proportional-integral-derivative (PID) controller. The PID controller is configured to individually control the temperature of the devices in different carriers.

[0014] Any two or more of the features described in this specification (including this Summary) may be combined to form implementations not specifically described herein.

[0015] The systems and techniques and technologies described herein, or a portion thereof, may be implemented as or controlled by a computer program product that includes instructions stored on one or more non-transitory machine-readable storage media and that may be executed on one or more processing devices to control (e.g., coordinate) the operations described herein. The systems and techniques and technologies described herein, or a portion thereof, may be implemented as an apparatus, method, or electronic system that may include one or more processing devices and a memory storing executable instructions for implementing various operations.

[0016] The details of one or more implementations are set forth in the accompanying drawings and the following detailed description. Other features, objects, and advantages will be apparent from the detailed description and drawings, and from the claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a perspective view of an exemplary testing system.

[0018] Figure 2 and Figure 3 is shown in different configurations during operation Figure 1 A perspective view of an example of the internal components of a testing system.

[0019] Figure 4 is a perspective view of an exemplary carrier for use in a testing system.

[0020] Figure 5 is a perspective view of an exemplary cover assembly mounted on a socket in an exemplary carrier.

[0021] Figure 6 is a cross-sectional side view of components of an exemplary socket cover that may be part of an exemplary closure assembly.

[0022] Figure 7is a side view of components of an example tool connected to an example socket cover.

[0023] Figure 8 is a cross-sectional side view of components of an example tool connected to an example socket cover.

[0024] Fig. 9 is a cross-sectional side view of components of an exemplary cover assembly.

[0025] Fig.10 An exploded perspective view of an exemplary slot in a testing system and a side view of an exemplary testing system showing internal components of the exemplary testing system are included.

[0026] Like reference numbers in different drawings indicate similar elements. DETAILED DESCRIPTION

[0027] This article describes an exemplary embodiment of a carrier-based test system. In addition to other components, an exemplary carrier-based test system includes a carrier having one or more test sockets, each test socket for receiving a device to be tested. The device being tested is referred to as a device under test or DUT. The test socket includes an electrical connector for connecting to the device. The system also includes a cover assembly assembled on the corresponding test socket. An exemplary cover assembly includes a socket cover. The socket cover is configured to contact the device in the test socket and apply pressure to electrically connect the device to the electrical connector in the test socket. These electrical connectors enable the test system to exchange signals with the device during testing. The socket cover is made of or includes a material (such as a metal) having a thermal conductivity exceeding a defined value. The exemplary cover assembly may include one or more structures, such as but not limited to fins, made of or including a material (such as a metal) having a thermal conductivity exceeding a defined value. Heat can be transferred from the device through the socket cover and the fins. The fin is configured to provide a surface area above which heat from the device is dissipated during testing or other appropriate times. For example, the thermal conductivity of the various components may be sufficient to dissipate heat from the device, in whole or in part, through the socket cover and outwardly through the fins.

[0028] The heat dissipation implemented in the exemplary carrier-based test system reduces the chance that the device will overheat and thus be damaged during the test, or the chance that the test will be adversely affected by the excess heat generated by the device. Therefore, the carrier-based test system can test devices operating at relatively high power, which typically generate more heat than devices operating at lower power. Examples of high-power devices include, but are not limited to, devices operating above 4 watts (W), above 10 W, above 20 W, etc. Some types of microprocessors can be characterized as high-power devices. However, the carrier-based test system is not limited to testing high-power devices or testing microprocessors, and can be used to test any appropriate device and dissipate heat from the device. As described below, the carrier-based test system can also be configured to add heat to the device.

[0029] Carrier-based test systems also use convection to assist in thermal control. In one example, one or more blowers are positioned to move air from a hot cavity (such as a cold cavity) over a carrier containing a device during testing. In some embodiments, the air is relatively cold and moves over and through the fins, thereby drawing heat from the fins and cooling the device. In some embodiments, a first blower (such as a fan) is positioned to direct thermal control air into the hot cavity. A second blower (such as a fan) is positioned in a test slot that accommodates the carrier. The two blowers operate to draw cold air from the hot cavity so that the cold air passes through and through the fins, thereby heating the cold air, and the resulting heated air is drawn out of the test slot and into the surrounding environment.

[0030] A carrier-based test system may be, but is not necessarily, a system-level test (SLT) system. System-level testing involves testing an entire device, rather than testing individual components of the device. If a device passes a series of system-level tests, it is assumed that the individual components of the device are operating properly. SLT has become more common as the complexity of devices and the number of components in the devices have increased. For example, a chip-implemented system, such as an application-specific integrated circuit (ASIC), may be tested at the system level to determine that the components comprising the chip are operating correctly.

[0031] In some embodiments, the exemplary test system is modular, so that the test system can adapt to various test requirements. Each unit of the test system is called a slice. Two or more slices can be combined and controlled to operate together (e.g., dependently) or independently to perform test operations.

[0032] See also Figure 1 and Figure 2, the exemplary test system 10 includes five levels (or zones) per slice; however, any appropriate number of levels may be included in the test system. In an exemplary embodiment, the five levels include an input / output (I / O) level 14, a transfer level 17, a loading level 18, an insertion level 19, and a test level 20. The definition of each level is not intended to be restrictive, and one or more components may perform functions in two or more of the levels. In some embodiments, different levels are configured to operate at different levels of precision. For example, a higher level of precision (e.g., up to the micron level) may be used in the loading level, while a lower level of precision may be used in some or all other levels. System components (such as mechanical components) may be configured to operate within tolerances to achieve lower levels of precision in some levels. By reducing higher precision to the level where it may be needed, the cost and complexity of the test system can be controlled in some cases.

[0033] Computing system 45 communicates with test system 10 to control and coordinate the operation of test system 10. Computing system 45 may include one or more processing devices, examples of which are described herein. Communication between test system 10 and computing system 45 is represented by dashed arrow 46.

[0034] The different stages of the test system can be operated independently and simultaneously. Figure 2 In the example of , each stage includes two parallel paths 21 and 22. Each of the parallel paths includes an automated device, such as a robot, that transfers carriers, devices, or both between adjacent stages. The operation of different stages independently, simultaneously, and in parallel paths can support higher test throughput and speed than some equivalent test systems.

[0035] exist Figure 1 In the example of , the I / O stage 14 includes, but is not limited to, a feeder for receiving trays of tested devices and for providing trays of untested devices to the test system. Figure 1In the example of , there are three feeders 23, 24, 25 per slice; however, the system is not limited to use with three feeders. The first feeder 23 is used for trays containing untested devices; the second feeder 24 is used for trays containing tested devices that have not passed the test, and the third feeder 25 is used for trays containing devices that have passed the test. In this example, the feeder 23 is manually loaded with trays of untested devices. A tray in a stack of trays containing untested devices is fed from the feeder 23 to the transport stage 17. After all devices on the tray have been forwarded for testing and the tray is empty, the tray is retracted into the feeder and a new tray containing untested devices is fed to the transport stage. After the device is loaded onto the tray after testing and the tray is full (in some embodiments), the tray is retracted into the feeder, and a new empty tray is fed from the I / O stage to the transport stage from either feeder 24 or 25. In this example, feeders 24 and 25 operate identically for trays containing devices that have passed testing and trays containing devices that have not passed testing.

[0036] In this example, the transfer stage 17 includes, but is not limited to, a transfer robot 30 (e.g., Figure 2 ) and two device shuttles 31, 32 (e.g., Figure 3 ). The two device shuttles provide parallel transfer paths into and out of the loading stage 18 described below and support test throughput and redundant reliability in some examples. The transfer robot 30 is controllable to load and unload the test equipment from a tray 34 (e.g., Figure 2 ) picks up the untested device and places the untested device into the device shuttle 31 and / or 32 (e.g., Figure 3 ). The transfer robot 30 is controllable to pick up the test device from the device shuttles 31 and 32 and place the test device into the appropriate one of the trays 35 or 36, depending on whether the particular device passed or failed the test. In some embodiments, the transfer robot 30 can pick up and hold the device by air suction or using a mechanical clamp or other mechanical mechanism.

[0037] In some embodiments, two device shuttles may be configured and controlled to operate in parallel, independently, simultaneously and / or in parallel. For example, a transfer robot may provide a device shuttle with a device to be tested, while removing a tested device from another device shuttle. The two device shuttles may be configured to move independently, in parallel, simultaneously and / or in parallel between a loading stage and a transmission stage. For example, one device shuttle may transfer a device to be tested from a transmission stage toward a loading stage, and transfer it to the loading stage, while another device shuttle transfers a tested device away from the loading stage, and transfers it to the transmission stage. In addition, one device shuttle may be stationary, while another device shuttle is moving. For example, one device shuttle may receive a device to be tested, while another device shuttle transfers the device to the loading stage or transfers the device from the loading stage.

[0038] In some embodiments, the loading stage 18 includes, but is not limited to, loading robots 48, 49 and areas for loading devices into and unloading devices from a test carrier (such as 50 and 51). In this example, there are two loading robots per slice; however, the test system may include any suitable number of loading robots. In this example, the loading robots 48, 49 are configured to move in the X dimension and also in the Z dimension to perform pick and place operations on the devices. For example, an untested device is picked up from a shuttle and moved to a carrier for testing, and a tested device is picked up from a carrier and moved to a shuttle.

[0039] exist Figure 2 and Figure 3 In the example of FIG, two test arms 77, 78 are shown per slice; however, the test system may include any suitable number of test arms. The test arms can move in all three dimensions (X, Y, and Z), including rotation and flipping, to insert test carriers containing untested devices into test slots in the test rack and extract or remove test carriers containing tested devices from test slots in the test rack. The carriers containing tested devices are moved back to the loading stage, where the devices are unloaded onto the shuttle by the loading robot.

[0040] Each test arm is configured to hold two test carriers simultaneously, one on each face or side of the test arm. In some embodiments, each side of the test arm (e.g., 77 or 78) includes a carrier holding container, such as a clamp, for receiving, holding and releasing the test carrier. In one example, the clamp is spring loaded to accept a test carrier containing an untested device from a carrier shuttle, and release the test carrier containing a tested device to a (same or different) carrier shuttle. The carrier shuttle can be configured to control the opening and closing of each clamp. The carrier shuttle 82 can move the carrier between the test arm and the loading position.

[0041] The test rack 80 includes a plurality of test slots. The carrier 81 is shown in the corresponding slot of the test rack. Each test slot can be configured and controlled to test the device in the test socket on the test carrier, and the test results are reported back to the computing system controlling the test system. The computing system tracks which devices have passed the test and which devices have failed the test, classifies the devices accordingly and reports the test results. The test slots in the test rack are served by the test arm. In some embodiments, during the test, except for a short time during the exchange of the test carrier in the slot, the test slot always remains occupied. For example, the test arm 77 or 78 can reach the test slot while maintaining the test carrier containing the untested device, extract the test carrier containing the tested device from the test slot, and insert the test carrier containing the untested device into the same test slot from which another test carrier is extracted. Therefore, except for the time between removing and inserting the test carrier, the test slot is still occupied. It is possible to provide services for each test slot in the test rack in this way to improve the test throughput. The following provides an example of how to insert and extract the test carrier.

[0042] In operation, the test arm 77 or 78 moves (e.g., flips and rotates) to position itself to pick up a test carrier containing an untested device from a carrier shuttle such as the carrier shuttle 50, and deposit the test carrier containing a tested device onto the (same or different) carrier shuttle. In this example, the test carrier is rotated (e.g., about 180°) and flipped. The rotation is around the longitudinal axis of the test arm, and the flipping includes a rotation in the X dimension. Due to this movement, the first gripper above the test arm is in a suitable position to pick up a test carrier containing an untested device from the carrier shuttle. Therefore, the first gripper is controlled to pick up a test carrier containing an untested device from the carrier shuttle. Then, the test arm rotates at a point above or near the carrier shuttle along its longitudinal axis to position the test carrier containing the tested device to be deposited onto the carrier shuttle. The second gripper holding the test carrier on the test arm is opened, so that the test carrier containing the tested device is deposited on the carrier shuttle. Then, the carrier shuttle transfers the test carrier containing the tested device to the loading stage.

[0043] Therefore, at this time, the second clamp is empty and the first clamp holds the test carrier containing the untested device. Therefore, the test arm rotates and flips to position the test arm to provide service for the test slot. The test arm can also move vertically to position itself in front of the target test slot to be serviced. This rotation and flipping is opposite to the rotation and flipping performed by positioning the test arm above the carrier shuttle. Therefore, the test arm is positioned to extract or receive the test carrier containing the tested device from the target test slot. The test carrier containing the tested device is received in the second clamp that was previously empty. After receiving the test carrier containing the tested device, the test arm rotates to position the test carrier in the first clamp containing the device that has not been tested to an appropriate position to be inserted into the same test slot. Then, the test carrier containing the device that has not been tested is pushed into the test slot, and the above operation is repeated slot by slot.

[0044] Similar to Figures 1 to 3 An exemplary embodiment of the system is described in U.S. Patent Application No. 15 / 688,112, entitled "Calibration Process For An Automated Test System," filed on August 28, 2017. U.S. Patent Application No. 15 / 688,112 is incorporated herein by reference. For example, the robot and other components of the input / output (I / O) stage 14, the transfer stage 17, the loading stage 18, the insertion stage 19, and the test stage 20 are incorporated into this application by reference from U.S. Patent Application No. 15 / 688,112.

[0045] Figure 4 An example of a test carrier 56 is shown. In some embodiments, the test socket and the electronic device are included in the test carrier, which is self-contained, portable and removable. In some embodiments, the test carrier includes an electrical interface that can be configured to connect to the device in the test carrier. For example, the interface can be configured to connect to a variety of different electrical interfaces. Figure 4 In the example of FIG. 5 , the test carrier 56 comprises two test sockets 58 , 59 arranged along the longitudinal dimension of the test carrier. Figure 4 In the example of FIG. 1 , two test sockets are shown, but other embodiments of the test carrier may include more or less than two test sockets. Each test socket may hold a corresponding device.

[0046] In some embodiments, the test socket is device-specific. For example, the test socket may include electrical contacts that are complementary to corresponding electrical contacts on a device under test (DUT). Among other things, the loading robot may be configured to place an untested device into the test socket and remove a tested device from the test socket. The test socket is embedded in a test carrier and includes a wall that guides the device under test to an appropriate position so that the electrical contacts in the carrier test socket are aligned with the electrical contacts on the device under test. In some embodiments, for example, where the electrical contacts are relatively large, the loading robot may not require a high level of precision, and the test socket wall may play a significant role in guiding the device under test to an appropriate position so that the electrical contacts in the carrier test socket are aligned with the electrical contacts on the device under test.

[0047] After the untested device reaches a resting position within the test socket, a socket cover is placed over the test socket, among other things, to apply pressure to the device so that electrical contacts in the device under test mate with complementary electrical contacts in the test carrier. In some embodiments, the socket cover may include a memory storing executable instructions that can be used by the device during testing. For example, the executable instructions may include operating instructions, test routines, etc. Thus, the socket cover may also include electrical contacts that mate with complementary electrical contacts on the device and / or the test carrier. In some embodiments, the socket cover applies force on the device to achieve various electrical connections; any appropriate amount of force may be applied to achieve the connection. In some embodiments, as described herein, the socket cover may be or include a kinematic base that applies force via a compression spring.

[0048] The socket cover may be part of a cover assembly that includes one or more structures, such as but not limited to fins, configured to provide a surface area over which heat from the device may be dissipated during testing. Figure 5 An example of a cover assembly 60 is shown in FIG. Fig. 9 A cross section of an exemplary cover assembly is shown in FIG. In this example, the cover assembly 60 includes a socket cover 61 and a fin 62. Fig. 9 In the example of FIG. 1 , one or more structures 67 contact the device in the socket and form a thermal connection with the fins. A frame 69 surrounds or defines the device in the socket.

[0049] In this regard, the socket cover is configured to physically contact a device in a corresponding test socket, as described herein. The connection includes a thermal connection between the cover assembly and the device in the test socket. In some embodiments, the thermal connection enables heat to be drawn from the device in the test socket. Heat can be drawn from the device during, after, or before testing. The socket cover is physically connected to a structure such as fins 62. Although Figure 5 and Fig. 9In the example, fins are shown, but any suitable structure may be used instead of or in addition to the fins. In this example, the fins are configured (e.g., shaped or arranged) so as to increase the surface area available for heat dissipation relative to the same type of socket cover without fins. In this example, the fins extend vertically relative to the top plate 63 of the socket cover. In this example, the fins are arranged along the longitudinal dimension of the socket cover. In this example, two groups of fins are used: a first group of fins 62a on the first edge of the socket cover and a second group of fins 62b on the second edge of the socket cover. In this example, the individual fins on each side are spaced equidistantly from each other to form a row of fins. In this example, each of the fins is made of or includes a thermally conductive material (such as a metal). Examples of materials that can be used for fins include, but are not limited to, aluminum, stainless steel, and graphite. In this example, each fin has approximately the same size, shape, and composition. In this example, the fins on each edge include fins extending from both sides of the socket cover. For example, the first set of fins 62a includes fins 64 extending upward from the socket cover 61 when the socket cover 61 is placed on the carrier and fins 65 extending downward from the socket cover 61 when the socket cover 61 is placed on the carrier.

[0050] In some embodiments, the fin is an integral part of the socket cover. For example, the fin and the socket cover can be formed (e.g., molded) together and form a single continuous structure. In some embodiments, the fin is not an integral part of the socket cover. In such embodiments, the fin can be subsequently fixed to the socket cover to form a cover assembly.

[0051] Despite Figure 5 and Fig. 9 The specific configuration of the fins on the cover assembly has been shown and described above, but the fins may have any suitable size, shape, arrangement, composition and configuration. For example, the fins are relative to Figure 5 The surface area shown may have an increased surface area. There may be more fins than shown or fewer fins. The individual fins may be made of different materials. The fins may be made of a different material than the socket cover 61, or made of the same material as the socket cover 61. There may be more than two rows of fins. Where appropriate, the rows of fins may extend over the entire lateral dimension of the socket cover.

[0052] As described above, the fins may be made of or include a thermally conductive material. The material may have any suitable thermal conductivity. For example, the thermal conductivity of each fin or some of the fins may be or exceed a predetermined value of 5 Watts / meter-Kelvin (W / mK), 6 W / mK, 7 W / mK, 8 W / mK, 9 W / mK, 10 W / mK, 11 W / mK, 12 W / mK, 13 W / mK, 14 W / mK, 15 W / mK, or 16 W / mK.

[0053] In some embodiments, the socket cover may include a conductive temperature control device in addition to the convection temperature control system implemented by the fins and blowers. For example, the socket cover may include a heater (such as one or more heating elements) to add heat to the device covered by the socket cover in the carrier. For example, the socket cover may include a Peltier device to absorb heat from the device covered by the socket cover in the carrier, thereby cooling the device.

[0054] In some embodiments, the entire cover assembly (including the socket cover and fins) is installed on or removed from the socket in the carrier. That is, the socket cover and fins are not usually installed on the carrier separately. Instead, in one operation or a group of operations, as described below with respect to Figures 6 to 8 As described, a single cover assembly is installed into or removed from a socket in a carrier. Figures 6 to 8 The fins are omitted to illustrate components of an exemplary socket cover.

[0055] See also Figure 6 In some embodiments, the socket cover 61 may be or include a kinematic base that applies force to the device in the test socket via a compression spring. In some embodiments, the kinematic base is built into the top of the socket cover, and an air floating bearing is used to float the test carrier during docking of the kinematic base. In some embodiments, the kinematic base is a purely mechanical mechanism for accurately aligning the test socket and the test socket cover. In some embodiments, after alignment with the kinematic base, a vacuum system is used in the same air bearing to suck (e.g., tighten) and fix the test carrier during loading and unloading of the device from the test carrier. In some embodiments, as described above, the test carrier contains two test sockets, and a separate socket cover can be attached to each test socket. In some embodiments, the socket cover floats during the connection (or latching) process, so that the action of connecting the socket cover to the test socket does not interfere with the device position during the precise placement of the socket cover. In this regard, the tool ball can be lowered to an arbitrary height, and the test carrier can then be floated upward to enable the tool ball to align the socket cover to the socket cover actuator. In some embodiments, such flotation ensures that vertical tolerances in the test carrier do not cause excessive downward force to be applied to the socket cover and, in turn, to the circuit board within the test carrier, which could cause micro-strain fractures of copper traces within the circuit board within the test carrier. In some embodiments, once the test carrier is aligned to its unique position, the position is maintained by applying negative pressure to the flotation mechanism (e.g., by drawing air to create a vacuum), thereby securing the test carrier to the base of the carrier shuttle.

[0056] As described, the socket cover is configured to contact a device in a test socket of a test carrier and, in response to pressure, electrically connect the device to an electrical connector in the test carrier and / or in the socket cover. The actuator is movable relative to the socket cover to engage the socket cover so that the socket cover can apply pressure as described herein. The actuator may include a key element and a tool ball. See also Figures 5 to 8 , the socket cover 61 includes a top plate 63 having grooves 66a, 66b, 66c, 66d, 66e and 66f, which are configured and arranged to engage corresponding tool balls. The top plate includes a hole 68, which has a shape complementary to the key element to allow the key element to pass through the hole when the key element is in the correct orientation.

[0057] See also Figure 6 and Figure 8 , the exemplary socket cover also includes a central plunger 104 that can be engaged by a key element. The central plunger 104 includes a hole to receive the key element through the top plate. Figure 8 , the key element and the plunger hole have complementary shapes 97 to allow the key element to pass through the plunger hole when the key element is in the correct orientation. The key element is configured to rotate in the plunger hole to rotate to engage the notch in the plunger. That is, when rotated within the plunger hole, the key element cannot slide out of the hole, but is connected to the plunger and causes the plunger to move in response to the upward force. The socket cover also includes a compression spring 106 controlled by an actuator.

[0058] The actuator 107 may include a rotatable key element 109, a tooling ball such as 110, 111, 112 arranged relative to the key element; and a block 114 to which the tooling ball is fixed. The key element is movable through the block and is movable relative to the tooling ball. See Figure 7 and Figure 8 , the actuator 107 is controllable to move the key element into the plunger 104 and rotate the key element within the plunger 104. At the same time, the tool ball engages the groove. For example, Figure 7 A tool ball 110 is shown engaging groove 68c. Other tool balls 111, 112 engage other grooves, although those other grooves are Figure 7 104. Then, in this example, the actuator is controlled to push the tool ball downward against the groove and pull the key element upward together with the plunger 104. This causes the compression spring 106 in the socket cover to compress. With the compression spring compressed in this way, the socket cover can be placed accurately over the device in the test socket without applying significant force. Once the socket cover is in place, the appropriate force can be applied by releasing the compression spring.

[0059] The actuator may be part of a test socket picker head of a loading robot. The test socket picker head places a socket cover over a test socket containing an untested device. The socket cover includes flanges 118, 119 which physically hold the socket cover in place in the test socket. After the socket cover is physically connected to the test socket via the flanges, the actuator is released, which causes the compression spring to release and apply a force downward. This force is sufficient to make a connection between a test carrier, device and / or storage in the socket cover. See, for example, Figure 6 , the socket cover may include a memory stack 122 containing pins that connect to complementary pins on the upper surface of the device to be tested, for example, through an interposer 124. The compressive force of the spring enables connection of these pins to the device and connection of the pins on the device to complementary pins on a circuit board on the test carrier and below the device to be tested.

[0060] In some embodiments, the interposer may be made of or include a thermally conductive material. The material may have any appropriate thermal conductivity. For example, the thermal conductivity of each fin or some of the fins in the fin may be or exceed 5 watts / meter-Kelvin (W / mK), 6W / mK, 7W / mK, 8W / mK, 9W / mK, 10W / mK, 11W / mK, 12W / mK, 13W / mK, 14W / mK, 15W / mK, 16W / mK, etc. Any appropriate material may be used, including but not limited to metal or graphite. The interposer may directly contact the device in the test socket, or the interposer may contact the device through one or more appropriate thermally conductive structures. The interposer may directly contact the fin, or the interposer may contact the fin through one or more appropriate thermally conductive structures. In any case, the resulting thermal connection between the device and the fin produces the heat transfer described herein, and enables the device to cool, or in some cases, to heat.

[0061] Fig.10 An example of a test slot 85 that can be used in a carrier-based test system is shown. In this example, a single test slot 85 accommodates two carriers 86 and 87. However, this is not required. In some embodiments, a single test slot can accommodate a single carrier, and in some embodiments, a single test slot can accommodate more than two carriers. As shown, the exemplary carrier 86 is inserted into the test arm (such as Figure 3 The test arm 77 or 78 of the carrier 86 is inserted into the test slot. The test slot includes an electrical interface (not shown) that mates with a corresponding electrical interface 88 in the test slot 85. Thus, electrical signals can be exchanged between the test system and the device held in the corresponding socket in the carrier 86 (e.g., during testing), as described herein. The carrier 87 forms a similar connection with the electrical interface 91.

[0062] The test slot 85 includes blowers 93 and 94 (such as fans or blowers) to move air over and through the fins of the cover assembly, thereby absorbing heat from the fins and cooling the device. As described below, heated air may also be moved over and through the fins, where appropriate. In this example, there are two blowers, one for servicing each carrier in the test slot 85. In some embodiments, there may be one blower per carrier or more than one blower per carrier. Any suitable number of blowers may be used to serve the test slots.

[0063] Fig.10 It also shows Figure 1 . A side view of an exemplary carrier-based test system 10. In this example, a test slot 85 is assembled into the carrier-based test system 10 at position 95. In this example, the carrier-based test system includes a test rack for holding the test slot and a plurality of other test slots. As described below, the carrier-based test system includes one or more blowers (such as a blower or fan) configured to circulate air around the test slot so as to cool the device held in the carrier. In this example, the carrier-based test system 10 includes a thermal cavity 96. In some embodiments, the thermal cavity is a thermally controlled chamber containing air maintained at a certain temperature, which in some cases is lower than a predetermined temperature. In some embodiments, the air in the thermal cavity may be at ambient temperature. For example, the temperature may be between 20 degrees Celsius (°C) and 25°C. However, the air temperature is not limited to these values. The air in the thermal cavity may be at any suitable temperature that can be used to cool the device in the test slot by convection. In some embodiments, the temperature of the air in the thermal cavity may exceed the temperature of the device held in the carrier. In this example, the heated air can move toward the test slot to heat the device held in the carrier. That is, the heated air can transfer heat to the fins of the capping assembly and increase the temperature of the device in the carrier.

[0064] exist Figure 1 and Fig.10 In an example of a test rack, air can be transferred from inside or outside the test system to the hot cavity through an anteroom 97 below the test rack. For example, one or more blowers (such as hair dryers and fans) and a heat exchanger can be used to cool the air and move the cooled air from the anteroom to the hot cavity. In some embodiments, the hot cavity can be insulated and airtight or substantially airtight to reduce the chance of thermal control air in the hot cavity leaking into the environment, significantly changing the temperature, or both. Arrow 98 conceptually illustrates an exemplary air flow path from the anteroom through the hot chamber and over the test slots.

[0065] Fig.10Also shown is the path of air through the test slot 85 using arrow 99. In this example, air from the hot cavity passes through the bracket containing the test slot 85. The air flow generated by the blower on or near the test rack and in the slot produces air circulation. In this example, the circulation moves air (such as ambient air) from the hot chamber over and through the fins of the cover assembly of the test socket, thereby absorbing heat from the fins and cooling the device covered by the cover assembly. In the case of heating, the air increases the temperature of the device via the fins. In one example, the air discharged from the test slot can be cooled (or heated) and is sucked back into the heat chamber via the blower and heat exchanger located in the front chamber 97. In some embodiments, the temperature of the air discharged from the test slot may be 40°C to 60°C. The temperature of the exhaust air may depend on the temperature of the air introduced into the slot, the heat absorbed from the device in the slot, or both.

[0066] In some embodiments, the cooling water flow of the blower in the chamber 97 and in the test slot and the heat exchanger can be computer controlled using a "PID" (proportional-integral-differential) control system loop. The PID control system loop can also be used to computer control the current through the electric heater located in the carrier. Each PID control system loop can be implemented using control software and an electric control circuit board in the carrier or in the test slot circuit board and the bracket monitoring circuit board. The PID control system continuously calculates an error value based on the difference between the target value and the measured value. The PID controller applies corrections to the measured value based on proportional, integral and differential terms to make the measured value closer to the target value. In this example, the measured value is the device temperature. Therefore, the system enables, for example, individual temperature control of various devices in the system on a device-by-device or carrier-by-carrier basis.

[0067] The exemplary processes described herein may be implemented and / or controlled using one or more computer systems including hardware or a combination of hardware and software. For example, a system similar to the system described herein may include various controllers and / or processing devices positioned at various points in the system to control the operation of the automation elements. A central computer may coordinate the operations in the various controllers or processing devices. The central computer, controllers, and processing devices may execute various software routines to achieve control and coordination of the various automation elements.

[0068] The example processes described herein may be controlled at least in part using one or more computer program products, e.g., one or more computer programs tangibly embodied in one or more information carriers (such as one or more non-transitory machine-readable media) for execution by or to control the operation of one or more data processing devices, e.g., a programmable processor, a computer, multiple computers, and / or a programmable logic component.

[0069] A computer program may be written in any form of programming language, including compiled or interpreted languages, and may be deployed in any form, including as a stand-alone program or as a module, component, subroutine, or other unit suitable for use in a computing environment. A computer program may be deployed to be executed on one computer or on multiple computers at one site or distributed across multiple sites and interconnected by a network.

[0070] The actions associated with implementing all or part of the test may be performed by one or more programmable processors that execute one or more computer programs to perform some of the functions described herein. All or part of the test may be implemented using dedicated logic circuits such as FPGAs (field programmable gate arrays) and / or ASICs (application specific integrated circuits).

[0071] Processors suitable for computer program execution include, for example, both general and special purpose microprocessors, and any one or more processors of any kind of digital computer. Typically, the processor will receive instructions and data from a read-only storage area or a random access storage area or both. Elements of a computer (including a server) include one or more processors for executing instructions and one or more storage area devices for storing instructions and data. Typically, a computer will also include (or be operatively coupled to receive data from it or transmit data to it or both) one or more machine-readable storage media, such as a mass storage device for storing data, for example, a magnetic disk, a magneto-optical disk, or an optical disk. Machine-readable storage media suitable for embodying computer program instructions and data include all forms of non-volatile storage areas, including, by way of example, semiconductor storage area devices, such as EPROM, EEPROM, and flash storage area devices; magnetic disks, such as internal hard disks or removable disks; magneto-optical disks; and CD-ROM and DVD-ROM disks.

[0072] As used herein, any "electrical connection" may imply a direct physical connection, or a wired or wireless connection that may or may not include intermediate components but still allows electrical signals to flow between the connected components. Unless otherwise specified, any "connection" involving a circuit that allows signal flow is an electrical connection, not necessarily a direct physical connection, regardless of whether the term "connection" is modified by "electrical".

[0073] The elements of different specific implementations described herein can be combined together to form other embodiments that are not specifically illustrated above. Multiple elements can be excluded from the structure described herein without adversely affecting its operation. In addition, each individual element can be combined into one or more single elements to carry out the function described herein.

Claims

1. A testing system comprising: a carrier, the carrier comprising a test socket for receiving a device to be tested, the test socket comprising an electrical connection; and A cover assembly, the cover assembly comprising: a socket cover for contacting the device to apply pressure to electrically connect the device to the electrical connector, the socket cover comprising a material having a thermal conductivity exceeding a defined value; and one or more structures configured to provide a surface area over which heat from the device is dissipated, the one or more structures comprising a material having a thermal conductivity exceeding the defined value; The one or more structures include fins that extend upward against the socket cover and downward against the socket cover at an edge position away from the socket cover and only extend upward against the socket cover at a center position near the socket cover, and wherein the cover assembly is configured to be mounted above the device and embedded in the carrier. 2 . The test system of claim 1 , wherein the fin is thermally connected to the device via the socket cover, the fin extending away from the device. 3 . The test system of claim 1 , wherein the fins are thermally connected to the device via the socket cover, the fins being arranged in one or more rows.

4. The testing system of claim 1, wherein the fins and the socket cover are integrated into a single structure comprising the cover assembly. 5 . The testing system of claim 1 , wherein the fin is thermally connected to the device via the socket cover, the fin comprising metal. 6 . The test system of claim 1 , wherein the fin is thermally connected to the device via the socket cover, the fin being metal.

7. The test system according to claim 1, further comprising: A test slot is configured to receive the carrier, the test slot including an interface to which the carrier is electrically connected, the test slot including an air mover configured to move air over the cap assembly.

8. The test system according to claim 7, further comprising: a thermal control chamber, the thermal control chamber comprising air maintained at a certain temperature; and A test rack is used to hold the test slot between a plurality of test slots, the test rack including one or more blowers configured to move air into the thermal control chamber.

9. The testing system of claim 8, wherein the temperature is ambient temperature.

10. The test system of claim 1, wherein the test socket is a first test socket, the device is a first device, and the carrier includes a second test socket for holding a second device to be tested.

11. The test system according to claim 1, further comprising: a test slot, the test slot being used to receive the carrier, the test slot comprising an interface to which the carrier is electrically connected; and A robot is provided for moving the carrier into and out of the test slot.

12. The test system according to claim 1, further comprising: An actuator is configured to engage the socket cover to place or remove the socket cover over the device.

13. The testing system of claim 12, wherein the actuator comprises: a key element, the key element being rotatable; a tool ball disposed relative to the key element; and A block, the tool ball is fixed to the block, and the key element passes through the block and is movable relative to the block.

14. The test system of claim 13, wherein the socket cover comprises a kinematic base, the kinematic base comprising: a first structure including a recess configured and arranged to engage the tooling ball, the first structure having a hole, the hole and the key element having complementary shapes to allow the key element to pass through the hole; a second structure having a hole, the hole and the key element having complementary shapes to allow the key element to pass through the hole, the key element being configured to rotate to engage the second structure; and At least one compression spring, the at least one compression spring being controllable by the first structure and the second structure.

15. The test system of claim 14, wherein the actuator is configured to cause an operation comprising: the actuator engaging the socket cover thereby forcing the tooling ball against the recess and causing the key element to pass through the first structure and the second structure; The actuator rotates the key element; the key element is pulled against the second structure while the tool ball is pushed against the groove to compress the compression spring; the actuator moves the socket cover into position over the device so that the socket cover is connected to the carrier; and After the socket cover is connected to the carrier, the actuator is retracted.

16. A testing system comprising: a cavity containing air maintained at a certain temperature; a test slot configured to receive the air from the cavity, the test slot comprising at least one blower for moving the air from the cavity through the test slot; a carrier having test sockets for insertion into the test slots, each test socket for receiving a device to be tested, the carrier comprising a cover assembly, the cover assembly comprising a socket cover and fins thermally connected to the device, the fins for providing a surface area over which heat from the device is dissipated, the fins comprising a material having a thermal conductivity exceeding a defined value; wherein the at least one blower is configured to move the air across the fins; and The fins extend upward against the socket cover and downward against the socket cover at an edge position away from the socket cover and only extend upward against the socket cover at a center position near the socket cover, and the cover assembly is configured to be mounted above the device and embedded in the carrier.

17. The testing system of claim 16, wherein the fin extends away from the device.

18. The testing system of claim 16, wherein the fins are arranged in one or more rows.

19. The testing system of claim 16, wherein the fin comprises metal.

20. The testing system of claim 16, wherein the fins are metal.

21. The test system of claim 16, wherein the socket cover is configured to fit over the device in the test socket; Wherein the fins and the socket cover are a single component comprising the cover assembly.

22. The test system of claim 16, wherein the test system comprises a plurality of test slots, each of the plurality of test slots being configured to receive a separate carrier, each carrier being configured to hold one or more devices; and The test system further includes a control system including a proportional-integral-derivative (PID) controller for individually controlling the temperature of the devices in different carriers.

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