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EP-4286862-B1 - BURN-IN STATION FOR PERFORMING BURN-IN TESTING OF ELECTRONIC DEVICES

EP4286862B1EP 4286862 B1EP4286862 B1EP 4286862B1EP-4286862-B1

Inventors

  • AMELIO, GIUSEPPE

Dates

Publication Date
20260506
Application Date
20220531

Claims (10)

  1. A burn-in station (BIS) (10) for performing burn-in testing of electronic devices, comprising: a main frame (11); at least one burn-in driver (BID) (100) embedded in the main frame (11) and including a plurality of slots (103); wherein each of the slots (103) receives a burn-in board (BIB) (135) meant to accommodate a plurality of devices to be tested; wherein each of the slots (103) comprises a slot cover (133) which, in an operative condition, tops the BIB (135) to define a slot chamber enclosing the devices to be tested;wherein each slot cover (133) comprises heating means meant to heat the underlying slot chamber; wherein said slot cover (133) further comprises cooling means meant to cool down the underlying slot chamber; wherein sealing elements are provided at each slot (103) to separately seal each slot chamber from its outside environment. wherein the sealing elements are selectively activatable to close and open the slot chamber. characterized in that said cooling means are configured to be activated alternatively with respect to the heating means and in that the sealing elements are configured to close the slot chamber when the heating means are activated and to open the slot chamber when the cooling means are activated.
  2. The BIS (10) according to claim 1, wherein said heating means comprise a heater plate (134) embedded in the slot cover (133).
  3. The BIS (10) according to claim 2, wherein the slot cover (133) further comprises a heat insulating portion (138) above the heater plate (134).
  4. The BIS (10) according to one of claims 2 or 3, wherein the heater plate (134) features different heating zones (A, B) the heating of which can be independently controlled.
  5. The BIS (10) according to any of the previous claims, wherein said cooling means comprise a network of airflow passages (134c) meant to channel cold air within the slot chamber.
  6. The BIS (10) according to claim 5, wherein the airflow passages (134c) comprise a plurality of air outlets (134b) arranged in correspondence with a plurality of sockets (136) of the BIB (135), each socket being arranged to accommodate a single device to be tested.
  7. The BIS (10) according to one of claims 5 or 6, wherein the airflow passages (134c) comprise a plurality of air inlets (134a) from which cold air enters, said air inlets (134a) being provided on the two opposite lateral sides of the slot cover (133).
  8. The BIS (10) according to one of claims 5-8, wherein said airflow passages are arranged to be connected with a source of cold air, for instance a compressed air network.
  9. The BIS (10) according to any of the previous claims, wherein said sealing elements are inflatable sealing elements disposed on a perimeter of the BIB (135).
  10. The BIS (10) according to any of the previous claims, further comprising a controller (12) connected to each of the plurality of slots (103) through dedicated local control electronics (137a, 137b) and configured to generate command signals and analyze test results, wherein each of the local control electronics (137a, 137b) are external to the slot chamber.

Description

Technical field The present invention is generally directed to the field of burn-in, and more particularly to a burn-in station (BIS) for performing burn-in testing of electronic devices. Prior art Burn-in testing comprises testing an electronic device or a semiconductor device, such as, but not limited to, an integrated circuit, a computer chip, a memory chip or a system on a chip, for example, for an extended period of time under various conditions to determine if there are any problems with the electronic device before it is used in the field. In other words, the electronic devices can be stress tested to detect early failures thereby increasing the reliability of the electronic devices that are tested. After stress testing the devices are screened to determine if they passed the stress tests. Generally, burn-in of electronic devices is the acceleration of the life of the electronic devices using various combinations of voltage, temperature, and time. Burn-in predicts different quality levels of the electronic devices associated with time. Electronic device manufacturers typically use burn-in to estimate the lifetime of semiconductor devices. In addition, burn-in is also a quality measure to estimate the number and/or the type of defects in the electronic devices over time. Burn-in is also used to accelerate a device past infant mortality. Infant mortality is an initial phase of device life. A device with a short life usually fails early in its life during the phase of infant mortality. Once a device has passed this initial phase of life, the device is more likely to function for many more years. To burn-in a device, the device is usually housed into a socket on a burn-in board (BIB). The BIB is the large circuit board used to hold and route signal traces for all of the devices undergoing burn-in. The BIB typically has a number of sockets to accommodate multiple devices. The devices are plugged into the sockets on the BIB, which is transferred into a chamber for burn-in. A driver card for providing signals in a test mode entry sequence and clock signals to the devices under burn-in is mounted onto the BIB. Further, the BIB may be provided with power tabs coupled to bus-bar power chips when the BIB is loaded into a cart, which is secured to a housing and/or a power supply rack of the docking station. Moreover, the BIB may also include a LED for each socket. A device undergoing burn-in in the socket drives the LED such that the LED flashes if the device is running properly. However, the integration of the driver and other electronic components with the BIB will degrade the reliability of the burn-in system as the driver and the electronic components can be affected by the high temperature during the temperature stress test. As a consequence, it can in turn reduce the accuracy of the burn-in testing of the electronic devices. On the other hand, in general, a hot chamber, which is a test chamber, is used to test BIBs in a high temperature operating range that can range from the environment temperature (i.e., the ambient or room temperature) up to about +150 degrees Celsius for example. In this case, heating is provided by heating elements and forced air fans that circulate the heated air throughout the hot chamber. As all of the BIBs are arranged in a single hot chamber, it is not easy to guarantee an even temperature distribution throughout the chamber, and thus different BIBs at different positions can undergo different heating temperatures, resulting in a poor test result. In addition, when the BIBs are tested in a low temperature operating range, a separated cold chamber will be provided to perform the test under a low temperature ranging from the environment temperature down to about -40 degrees Celsius for example. There is also the defect of uneven temperature distribution. Moreover, the testing process is complicated, as different chambers should be provided for the high and low temperature testing. Documents CN 112 114 207 A and US 2021/255237 A1 show devices according to the prior art. Therefore, it is desired to provide an improved BIS for performing burn-in testing of electronic devices in order to overcome the drawbacks present in the prior art. Summary of the invention The technical problem outlined above is solved by a burn-in station (BIS) for performing burn-in testing of electronic devices, comprising: a main frame;at least one burn-in driver (BID) embedded in the main frame and including a plurality of slots;wherein each of the slots receives a burn-in board (BIB) meant to accommodate a plurality of devices to be tested;wherein each of the slots comprises a slot cover which, in an operative condition, tops the BIB to define a slot chamber enclosing the devices to be tested;wherein the slot cover comprises heating means meant to heat the underlying slot chamber. Preferably, said heating means comprise a heater plate embedded in the slot cover. Preferably, the slot cover further comprises a