Thermal solution for massively parallel testing

An apparatus for thermal control of a device under test (DUT) includes a cooling structure operable to provide cooling, the cooling structure operable to inlet cooling material via an inlet port thereof and operable to outlet cooling material via an outlet port thereof, a variable thermal conductance material (VTCM) layer disposed on a surface of the cooling structure, and a heater layer operable to generate heat based on an electronic control, and wherein the VTCM layer is operable to transfer cooling from the cooling structure to the heater layer. A thermal interface material layer is disposed on the heater layer. The thermal interface material layer is operable to provide thermal coupling and mechanical compliance with respect to the DUT. The apparatus includes a compression mechanism for providing compression to the VTCM layer to vary a thermal conductance of the VTCM layer. The compression mechanism is also for decoupling the VTCM layer from the heater layer.