Burn-in system with measurement block accomodated in cooling block

Abstract

A burn-in system enabling the temperatures of a large number of electronic devices differing in amount of self generated heat to be simultaneously reliably adjusted to a predetermined temperature, that is, a burn-in system bringing heater blocks having heaters, cooling blocks formed with channels able to carry a coolant, and sensor blocks having temperature sensors into contact with a plurality of DUTs mounted on a burn-in board and simultaneously performing a burn-in test on the plurality of DUTs, wherein each cooling block is formed with a first accommodating space and second accommodating space, each heater block is accommodated in a first accommodating space in a state maintaining clearance from the inside wall surfaces, and each sensor block is accommodated in a second accommodating space in a state maintaining clearance from the inside wall surfaces.

1 . A burn-in system for conducting a burn-in test on a device under test (DUT) mounted on a burn-in board, comprising:
 a cooling block formed with channel able to carry a coolant for cooling the DUT;   a measurement block having measuring device configured to measure the temperature of the DUT; and   a variable flow rate device configured to vary the flow rate of the coolant flowing through the channel,   bringing the cooling block and the measurement block into contact with the DUT and conducting a burn-in test on the DUT, wherein   the cooling block is formed with an accommodating space for accommodating the measurement block, and   the measurement block is accommodated in the accommodating space having a layer of air formed between the measurement block and the cooling block so as to be insulated from the cooling block.   
   
   
       2 . The burn-in system as set forth in  claim 1 , wherein
 the measurement block is supported and mechanically floating with respect to the cooling block, and   when the measurement block is not in contact with the DUT, a front end face of the measurement block sticks out relative to a front end face of the cooling block.   
   
   
       3 . The burn-in system as set forth in  claim 2 , wherein the system further comprises a first biasing device provided between the measurement block and the cooling block and configured to bias the measurement block to the front end face. 
   
   
       4 . The burn-in system as set forth in  claim 3 , wherein
 when the measurement block is not in contact with the DUT, the first biasing device cause the measurement block to be biased and cause part of the measurement block to contact the cooling block.   
   
   
       5 . The burn-in system as set forth in  claim 1 , wherein the system further comprises:
 a plurality of temperature adjustment boards supporting a plurality of the cooling blocks at a frame with mechanical floating; and   a burn-in chamber able to hold the burn-in boards, wherein   each of the temperature adjustment boards is provided in the burn-in chamber so that the each cooling block faces the DUT mounted on the burn-in board.   
   
   
       6 . The burn-in system as set forth in  claim 5 , wherein the each cooling block is supported on the frame through a second biasing device configured to bias the cooling block toward a burn-in board. 
   
   
       7 . The burn-in system as set forth in  claim 5 , wherein at least part of the channels formed at the plurality of the cooling blocks are connected in series. 
   
   
       8 . The burn-in system as set forth in  claim 7 , wherein the cooling block has-a bypass for making the coolant bypass the channel. 
   
   
       9 . The burn-in system as set forth in  claim 8 , wherein the variable flow rate device is provided in the channel or the bypass. 
   
   
       10 . The burn-in system as set forth in  claim 8 , wherein the temperature adjustment board has first cooling blocks formed with the bypasses and second cooling blocks not formed with the bypasses. 
   
   
       11 . The burn-in system as set forth in  claim 8 , wherein
 the plurality of temperature adjustment boards include one temperature adjustment board which has first cooling blocks formed with the bypasses and another temperature adjustment board which has second cooling blocks not formed with the bypasses.   
   
   
       12 . The burn-in system as set forth in  claim 5 , wherein the temperature adjustment board has at least two types of cooling blocks having different thermal resistances between the coolant and the DUT. 
   
   
       13 . The burn-in system as set forth in  claim 5 , wherein
 a thermal resistance between the coolant and the DUT in coolant blocks of one temperature adjustment board among the plurality of temperature adjustment boards and a thermal resistance between the coolant and the DUT in coolant blocks of another temperature adjustment board among the plurality of temperature adjustment boards are different.   
   
   
       14 . A temperature adjustment head comprising:
 a cooling block formed with channels able to carry a coolant for cooling the device under test (DUT);   a measurement block having a measuring device configured to measure a temperature of the DUT; and   a variable flow rate device configured to vary the flow rate of the coolant flowing through the channel, wherein   the cooling block is formed with an accommodating space for accommodating the measurement block, and   the measurement block is accommodated in the accommodating space having a layer of air formed between the measurement block and the cooling block so as to be insulated from the cooling block.