초록 ▼

A semiconductor-wafer chuck for heating and cooling a device-under-test includes a heat-spreader plate with a clamping surface for a semiconductor wafer. A heater is disposed within the heat-spreader plate. A chiller heat-exchanger provides for heat removal. A motion control system is used to move t

A semiconductor-wafer chuck for heating and cooling a device-under-test includes a heat-spreader plate with a clamping surface for a semiconductor wafer. A heater is disposed within the heat-spreader plate. A chiller heat-exchanger provides for heat removal. A motion control system is used to move the chiller heat-exchanger in relation to the heat-spreader plate, and thus provide for an adjustment of the thermal resistance and thermal coupling between the two. The heater comprises electric heating elements with a variable power input, and the chiller heat-exchanger is moved sufficiently far away to prevent boiling and evaporation of a coolant disposed inside. A device-under-test temperature controller controls the device-under-test temperature by adjusting the heater power, chiller fluid temperature and/or by moving the chiller heat-exchanger in relation to the heat spreader plate.

대표청구항 ▼

1. A semiconductor-wafer tester, comprising:a heat-spreader plate providing a clamping surface for a semiconductor wafer;a heater disposed within the heat-spreader plate and providing for temperature elevations;a chiller heat-exchanger mobile and independent of the heat-spreader plate and providing

1. A semiconductor-wafer tester, comprising:a heat-spreader plate providing a clamping surface for a semiconductor wafer;a heater disposed within the heat-spreader plate and providing for temperature elevations;a chiller heat-exchanger mobile and independent of the heat-spreader plate and providing for heat removal;a continuously variable-width gap separating the chiller heat-exchanger in relation to the heat-spreader plate providing for continuous thermal resistance and coupling adjustments of heat sinking out of said semiconductor wafer; anda position control system connected to adjust the continuously variable-width gap. 2. The semiconductor-wafer tester of claim 1, wherein:the heater comprises electric heating elements that can be power controlled including full on or off; andthe chiller heat-exchanger is moved sufficiently far enough away to prevent boiling and evaporation of a coolant disposed inside when the heater is under power. 3. The semiconductor-wafer tester of claim 1, further comprising:a device-under-test-temperature controller with electrical outputs connected to the heater and connected to the position control system, and having an input for sensing the temperature of a device-under-test clamped to the heat-spreader plate, and further providing for the control of said temperature by controlling the heater power and by moving the chiller heat-exchanger in relation to the heat-spreader plate. 4. The semiconductor-wafer tester of claim 3, further comprising:a limiter disposed in the device-under-test-temperature controller for limiting the movement of the chiller heat-exchanger in relation to the heat-spreader plate according to a maximum supportable heat load. 5. The semiconductor-wafer tester of claim 1, further comprising:a vacuum for clamping said semiconductor wafer to said clamping surface; andan external chiller connected to circulate coolant to the chiller heat-exchanger. 6. A means for heating and cooling a device-under-test, the method comprising the steps of:means for providing a heat-spreader plate with a clamping surface for a device-under-test;variable separation-gap positioning means for continuous adjustment between a minimum and a maximum of a thermal resistance from said heat-spreader plate to a chiller heat-exchanger;means for heating said heat-spreader plate by incrementally increasing said thermal resistance from it to a chiller heat-exchanger; andmeans for cooling said heat-spreader plate by incrementally decreasing said thermal resistance from it to said chiller heat-exchanger. 7. The means of claim 6, wherein:the means for heating is such that an increase in said thermal resistance to said chiller heat-exchanger is sufficient to prevent boiling of a coolant fluid circulating within said chiller heat-exchanger. 8. The means of claim 6, wherein:the means for heating is such that said chiller heat-exchanger is maintained at an idle temperature. 9. The means of claim 6, wherein:the means for cooling further includes using a chiller heat-exchanger in which is circulated a fluid comprising a fluorocarbon. 10. The means of claim 6, further comprising:means for limiting any heat loading of a chiller circulating a coolant to said chiller heat-exchanger by controlling a change in said thermal resistance. 11. The means of claim 6, further comprising:means for measuring the temperature of said heat-spreader plate; andmeans for controlling said thermal resistance to maintain a setpoint temperature according to information obtained in the step of measuring.